2005 entries 
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Beckmann, J   Costantino, F   Dakternieks, D   Duthie, A   Ienco, A
   Midollini, S   Mitchell, C   Orlandini, A   Sorace, L
Inorganic-organic hybrids of the p,p '-diphenylmethylenediphosphinate,
   pcp(2-). Synthesis, characterization, and XRPD structures of [Sn(pcp)]
   and [Cu(pcp)]
INORGANIC CHEMISTRY 44, 2005, 9416-9423.
Two new inorganic-organic polymeric hybrids
[Sn(pcp)] and [Cu(pcp)],    pcp = CH2(PhPO2)(2)(2-),
solved "ab initio" by X-ray powder diffraction (XRPD) data.


Vila, E   Iglesias, JE   Galy, J   Castro, A
Synthesis and characterization of a novel bismuth-molybdenum oxide and
   study of its ionic conducting behavior
The crystal data have been determined by ab
   initio indexing of the powder pattern.


Bestaoui, N   Xiang, OY   Fredoueil, F   Bujoli, B   Clearfield, A
Structural characterization of Cd-3(O3PC2H4CO2) (2). 2H(2)O
   from in-house X-ray powder data and NMR
   dihydrate], Cd-3(O3PC2H4CO2)(2) .  2H(2)O,
 structure determined from in-house powder data.
The structure was solved in both P2(1)/c and P2(1) space groups.


Burley, JC
Structure and intermolecular interactions of glipizide from laboratory
   X-ray powder diffraction
The crystal structure of glipizide, used as a major treatment of type-2
   diabetes, has been determined ab initio using variable-temperature
   laboratory X-ray powder diffraction combined with a direct-space Monte
   Carlo/simulated annealing methodology. The strengths of the
   intermolecular interactions (van der Waals, pi-pi stacking, hydrogen
   bonding and steric interlock) were quantitatively estimated using the
   thermal expansion data, which were collected in the same set of
   experiments as those used to determine the structure.

2005-7  ??

Rodriguez, A   Sakiyama, H   Masciocchi, N   Galli, S   Galez, N
   Lloret, F   Colacio, E
Hexacyanocobaltate(III) anions as precursors of Co(II)-Ni(II)
   cyano-bridged multidimensional assemblies: Hydrothermal syntheses,
   crystal and powder x-ray structures, and magnetic properties
INORGANIC CHEMISTRY 44, 2005, 8399-8406.
unconventional powder X-ray diffraction analyses


Bonhomme, F   Alam, TM   Celestian, AJ   Tallant, DR   Boyle, TJ
   Cherry, BR   Tissot, RG   Rodriguez, MA   Parise, JB   Nyman, M
Tribasic lead maleate and lead maleate: Synthesis and structural and
   spectroscopic characterizations
INORGANIC CHEMISTRY 44, 2005, 7394-7402.
[Pb4O3]C2H2(CO2)(2)(.)1/2H(2)O, solved ab initio from X-ray powder
   diffraction data,


Barbier, J   Penin, N   Denoyer, A   Cranswick, LMD
BaBiBO4, a novel non-centrosymmetric borate oxide
SOLID STATE SCIENCES 7, 2005, 1055-1061.
BaBiBO4 or BaBi(BO3)O, Pna2(1)
crystal structure determined from
   powder X-ray diffraction data and refined from powder neutron
   diffraction data


Kelm, K    Mader, W
Synthesis and structural analysis of epsilon-Fe2O3
epsilon-Fe2O3       Pna2(1)
ab initio, X-ray diffraction data of the powder containing
   small amounts of Al substituting Fe were refined by the Rietveld


Fukuda, K    Fukushima, K
Crystal structure of hexagonal SrAl2O4 at 1073 K
SrAl2O4 at 1073 K   -  P63 ,  Z = 6
determined from
conventional X-ray powder diffraction data using direct methods,
refined by the Rietveld method. The structure was hexagonal


Bhuvanesh, NSP   Reibenspies, JH   Zhang, YG   Lee, PL
A novel strategy for ab initio structure determination using
   micro-powder X-ray diffraction: structure solution and refinement of
   3-bromophenylboronic acid and tris(4-bromophenyl) boroxine
3-bromo-phenylboronic acid and
tris(4-bromophenyl) boroxine, were
   recorded with microgram quantities of sample using a recently developed
   method employing nylon loops with
synchrotron radiation and an image-plate detector.
The structures of the two
   compounds have been solved by ab initio methods using real-space
   techniques ( simulated annealing and/or parallel tempering) followed by
   Rietveld refinements with soft restraints on the bond lengths of the
   rigid bodies.
It is believed that this is the first time that powder X-ray
   diffraction patterns using microgram samples have been successfully
   employed for the structure solution and refinement of molecules with
   reasonable complexity.


Zhang, Y   Liu, QL   Li, JB   Liang, JK   Luo, J   Liu, FS   Xiao, YG   Rao, GH
Structures of the zeta and zeta ' phases in the Ag-Ga system
zeta-phase  P63/mmc   and
zeta'-phase : Ag2Ga (real composition Ag2+xGa1-x, x = 0.16)  P-6
   determined by X-ray powder diffraction and refined by Rietveld method.


Lefebvre, J   Willart, JF   Caron, V   Lefort, R   Affouard, F   Danede, F
Structure determination of the 1/1 alpha/beta mixed lactose by X-ray
   powder diffraction
mixed form of alpha/beta lactose
The X-ray powder diffraction pattern
   was recorded at room temperature with a sensitive curved detector (CPS
   120). The structure was solved by real-space methods ( simulated
   annealing) followed by Rietveld refinements with soft constraints on
   bond lengths and bond angles.
The width of the Bragg peaks is interpreted through a
   microstructural approach in terms of isotropic strain effects and
   anisotropic size effects.


Zhang, QA   Yang, WM   Akiba, E
Synthesis and crystal structure of a new ternary compound Ca4Al3Mg
Ca4Al3Mg    Pbcm
The crystal structure was determined by X-ray powder diffraction.


Fukuda, K   Moriyama, A   Iwata, T
Crystal structure, phase transition and anisotropic thermal expansion
   of barium zirconium diorthophosphate, BaZr(PO4)(2)
BaZr(PO4)(2) at 298 K   C2/m   Z = 2
determined from
   conventional X-ray powder diffraction data using direct methods, and it
   was further refined by the Rietveld method.


Tsirlin, AA   Chernaya, VV   Shpanchenko, RV   Antipov, EV   Hadermann, J
Crystal structure and properties of the new complex vanadium oxide
K2SrV3O9    Pnma and Z = 4.
investigated by means of X-ray powder diffraction (XPD)
refined by Rietveld    method using X-ray powder diffraction data.


Salvado, MA   Pertierra, P   Bortun, AI   Trobajo, C   Garcia, JR
New hydrothermal synthesis and structure of Th-2(PO4)(2)(HPO4)-H2O: the
   first structurally characterized thoriurn hydrogenphosphate
Th-2(PO4)(2)(HPO4)-H2O    P21, Z = 2
 solved by powder X-ray diffraction data


Shin, N   Kim, J   Ahn, D   Sohn, KS
A new strontium borophosphate, Sr6BP5O20, from synchrotron powder data
Strontium borophosphate, Sr6BP5O20, was prepared by a solution
   synthesis method. The crystal structure was solved ab initio from
   synchrotron powder data without preliminary knowledge of the chemical
   formula. The compound crystallizes in space group I (4) over bar c2. Sr
   atoms occupy sites coordinated by eight or nine O atoms, and the
   anionic layer consists of BO4 and PO4 tetrahedra. The
   eightfold-coordinated Sr atom lies at a site with twofold symmetry,
   while one P atom and the B atom are located on special positions of
   site symmetry (4) over bar.


Stahl, K   Balic-Zunic, T   da Silva, F   Eriksen, KM   Berg, RW   Fehrmann, R
The crystal structure determinations and refinements of K2S2O7, KNaS2O7
   and Na2S2O7 from X-ray powder and single crystal diffraction data
K2S2O7, C2/c  and  KNaS2O7
solved and/or refined from X-ray synchrotron powder diffraction data


Malpezzi, L   Magnone, GA   Masciocchi, N   Sironi, A
Single crystal and powder diffraction characterization of three
   polymorphic forms of Acitretin
Polymorphs of Acitretin :
   tetraenoic acid or
   3-methoxy-2-methyl-17-nor-1,2,3,4-tetradehydroretinoic acid],
three polymorphic modifications (hereafter, I, II, and III),

X-ray powder diffraction methods (form II
   and III) from conventional laboratory data only.
   real space techniques (simulated annealing and whole-profile pattern
   matching) have been employed.
These results show that ab initio
   structural studies from conventional laboratory X-ray powder
   diffraction (XRPD) data are fully providing the opportunity to
   investigate the structural aspects of moderately complex substances
   also in the absence of single crystals, disclosing the crystal
   chemistry of a few polymorphs of pharmaceutically relevant species.


Bestaoui, N   Bakhmutova-Albert, EV   Rodriguez, AV   Llavona, R   Clearfield, A
Ab-initio powder structure determination of
   dihydrate, Zn3Cl2(HO3PCH2NHCH2CH2NHCH2PO3H)(2) .  2H(2)O
P2(1)/n, Z = 4.
The crystal structure was determined ab initio from its powder pattern using
the programs EXPO and GSAS.


Fernandez-Carrasco, L   Puertas, F   Blanco-Varela, MT   Vazquez, T   Rius, J
Synthesis and crystal structure solution of potassium dawsonite: An
   intermediate compound in the alkaline hydrolysis of calcium aluminate
Potassium dawsonite KAI(CO3)(OH)2    Cmcm  Z = 4.
has been solved by
   direct methods from X-ray powder diffraction data and refined with the
   Rietveld method.


Ribas, X   Sironi, A   Masciocchi, N   Lopes, EB   Almeida, M   Veciana, J   Rovira, C
Structural, magnetic, and electrical characterization of new
   polycrystalline phases of nickel- and platinum-doped
   [(DT-TTF)n][Au(mnt)(2)] (n=1,2)
INORGANIC CHEMISTRY 44, 2005, 2358-2366.
determined using laboratory X-ray powder diffraction data.


Baies, R   Caignaert, V   Pralong, V   Raveau, B
Copper hydroxydiphosphate with a one-dimensional arrangement of copper
   polyhedra: Cu-3[P2O6OH](2)
INORGANIC CHEMISTRY 44, 2005, 2376-2380.
Cu-3(P2O6OH)(2)     P1
solved ab initio from X-ray powder diffraction data


Lu, J   Wei, S   Yu, WC   Zhang, HB   Qian, YT
TStructure and luminescence of 2D dilute magnetic semiconductors:
   Cd1-xMnxSe  .  L-0.5 (L = diamines)
CHEMISTRY OF MATERIALS 17, 2005, 1698-1703.
The two-dimensional (2D) dilute magnetic semiconductors
   (Cd1-xMnxSeL0.5)-L-. (L = ethylenediamine, or en, and
   1,6-hexanediamine, or hda, x = 0-0.8) were synthesized in an autoclave
   at 120 degrees C. Ab initio structure solution from X-ray powder
   diffraction reveals the host compound CdSe  .  hda(0.5) (space
   group, Pbca, a = 6.8852 angstrom, b = 6.7894 angstrom, c = 27.4113
   angstrom) is structurally analogous to CdSe  .  en(0.5), except
   for a subtle difference in alignment of aliphatic diamine ligands-the
   hda molecule deflects from the c axis and inclines toward the b axis.

Bonhomme, F   Larentzos, JP   Alam, TM   Maginn, EJ   Nyman, M
Synthesis, structural characterization, and molecular modeling of
   dodecaniobate Keggin chain materials
INORGANIC CHEMISTRY 44, 2005, 1774-1785.
Four new isostructural one-dimensional dodecaniobate Keggin materials,
   Na-12[Ti2O2][TNb1 2O40]-xH(2)O and Na-10[Nb2O2][TNb12O40]-xH(2)O with T
   = (Si or Ge), have been synthesized hydrothermally using a
   Lindqvist-ion salt, Na-7 [Nb6O19H]-15H(2)O, as the precursor. Their
   structure, consisting of chains of Keggin ions [TNb12O40](16-) linked
   by [Ti2O2](4+) or [Nb2O2](6+) bridges, was solved ab initio from powder
   diffraction data.


Gallo, E   Caselli, A   Ragaini, F   Fantauzzi, S   Masclocchi, N   Sironi, A   Cenini, S
Structural determination of ruthenium-porphyrin complexes relevant to
   catalytic epoxidation of olefins
INORGANIC CHEMISTRY 44, 2005, 2039-2049
A reproducible synthesis of a competent epoxidation catalyst,
   [Ru-VI(TPP)(0)(2)] (TPP = tetraphenylporphyrin dianion), starting from
   [Ru-II(TPP)(CO)L] (L = none or CH3OH), is described. The molecular
   structure of the complex was determined by using ab initio X-ray powder
   diffraction (XRPD) methods


Boldyreva, EV   Ivashevskaya, SN   Sowa, H   Ahsbahs, H   Weber, HP
Effect of hydrostatic pressure on the gamma-polymorph of glycine - 1. A
   polymorphic transition into a new delta-form
The results of a high-resolution powder diffraction study of the effect
   of high hydrostatic pressure up to 8 GPa on the pure gamma-polymorph of
   glycine (P3(1)) are discussed. A phase transition with a jumpwise
   change of cell volume and cell parameters was observed. The transition
   starts at about 2.73 GPa and is still not complete even at 7.85 GPa.
   The crystal structure of the previously unknown high-pressure polymorph
   of glycine (delta-polymorph) could be solved and refined in the space
   group Pn.


Platteau, C   Lefebvre, J   Affouard, F   Willart, JF   Derollez, P   Mallet, F
Structure determination of the stable anhydrous phase of alpha-lactose
   from X-ray powder diffraction
The stable anhydrous form of alpha-lactose has been obtained by the
   dehydration of alpha-lactose monohydrate in methanol. An Xray powder
   diffraction pattern was recorded at room temperature with a laboratory
   diffractometer equipped with an INEL curved sensitive detector CPS120.
   The starting structural model of this form was found by a Monte-Carlo
   simulated annealing method.


Barea, E   Romero, MA   Navarro, JAR   Salas, JM   Masciocchi, N   Galli, S   Sironi, A
Structure, spectroscopic properties, and reversible solid-to-solid
   reactions of metal complexes of 5-nitro-pyrimidin-2-olate
INORGANIC CHEMISTRY 44, 2005, 1472-1481.
In searching for coordination polymers containing the highly polarized
   5-nitro-pyrimidin-2-olate ligand (NP), a number of species containing
   3d transition metals have been prepared and characterized, namely
   Co(NP)(2)(H2O)(4), [Co(NP)(2)](n), Ni(NP)(2)(H2O)(4), Ni(NP)(2)](x),
   and [Zn(NP)(2)](n). Their structures have been determined by X-ray
   powder diffraction methods.


Ivashkevich, LS   Lyakhov, AS   Ivashkevich, DO   Degtyarik, MM   Gaponik, PN
Synthesis and crystal structure of the
   complex CuCl2(C2H4N4)(2)
The X-ray diffraction study of the CuCl2(C2H4N4)(2) complex, where
   C2H4N4 is 1-methyl-tetrazole, was carried out. The structure was solved
   ab initio using the X-ray powder diffraction data. The complex
   crystallizes in space group P2(1)/c, alpha = 11.2341(6) Angstrom, b =
   6.7272(3) Angstrom, c = 7.2149(3) Angstrom, 104.718(3)degrees, V
   527.36(4) Angstrom(3), Z = 2.


Ivashkevich, LS   Lyakhov, AS   Degtyarik, MM   Gaponik, PN
An X-ray powder diffraction study of
The crystal structure of the polymeric title complex,
   [CuBr2(C4H8N8)(2)](n), has been solved from X-ray powder data and
   refined with the Rietveld method using geometrical soft restraints.


Chernaya, VV   Mitiaev, AS   Chizhov, PS   Dikarev, EV   Shpanchenko, RV
   Antipov, EV   Korolenko, MV   Fabritchnyi, PB
Synthesis and investigation of Tin(II) pyrophosphate Sn2P2O7
CHEMISTRY OF MATERIALS 17, 2005, 284-290.
The crystal structure
   of the high temperature alpha-Sn2P2O7 form was solved using
   high-temperature powder diffraction data collected at 773 K. The
   structural motif of the high temperature form (monoclinic, P2(1)/n, a =
   7.1765(4) Angstrom, b = 9.2874(6) Angstrom, c = 5.2968(4) Angstrom,
   beta = 106.034(3)degrees, V = 339.30(5) Angstrom(3), Z = 2) is closely
   related to the room temperature modification.


Platteau, C   Lefebvre, J   Hemon, S   Baehtz, C   Danede, F   Prevost, D
Structure determination of forms I and II of phenobarbital from X-ray
   powder diffraction
From pure powders of forms I and II of phenobarbital, X-ray diffraction
   patterns were recorded at room temperature. The starting crystal
   structural models were found by a Monte-Carlo simulated annealing
   method. The structures of the two forms were obtained through Rietveld
   refinements. Soft restraints were applied on bond lengths and bond
   angles, all H-atom positions were calculated. The cell of form I is
   monoclinic with the space group P2(1)/n, Z = 12, Z' = 3. Form II has a
   triclinic cell, with the space group P (1) over bar, Z = 6, Z' = 3. For
   both forms, the crystal cohesion is achieved by networks of N - H ... O
   hydrogen bonds along [101]. The broadening of the Bragg peak profiles
   is interpreted in terms of isotropic strain effects and anisotropic
   size effects.


Derollez, P   Correia, NT   Danede, F   Capet, F   Affouard, F   Lefebvre, J   Descamps, M
Ab initio structure determination of the high-temperature phase of
   anhydrous caffeine by X-ray powder diffraction
The high-temperature phase I of anhydrous caffeine was obtained by
   heating and annealing the purified commercial form II at 450 K. This
   phase I can be maintained at low temperature in a metastable state. A
   powder X-ray diffraction pattern was recorded at 278 K with a
   laboratory diffractometer equipped with an INEL curved
   position-sensitive detector CPS120. Phase I is dynamically
   orientationally disordered (the so-called plastic phase). The Rietveld
   refinements were achieved with rigid-body constraints. It was assumed
   that on each site, a molecule can adopt three preferential orientations
   with equal occupation probability. Under a deep undercooling of phase
   I, below 250 K, the metastable state enters in a glassy crystal state.


Jorda, JL   Prokic, S   McCusker, LB   Baerlocher, C   Xue, CF   Jong, JX
Synthesis and structure analysis of the potassium calcium silicate
   CAS-1. Application of a texture approach to structure solution using
   data collected in transmission mode
COMPTES RENDUS CHIMIE 8, 2005, 331-339.
The crystal structure of the potassium calcium silicate material, CAS-1
   (|(Ca4K4(H2O)(8))|[Si16O38]), has been determined from
   synchrotron powder diffraction data collected on a textured
   polycrystalline sample. It was not possible to solve the structure
   directly from normal high-resolution powder diffraction data, so the
   newly developed texture approach to structure solution using data
   collected in transmission mode was applied. Data analysis was performed
   using the computer program Expol, which has been developed to handle
   the large amount of data generated in transmission mode. The structure
   could then be solved by direct methods, and Rietveld refinement (using
   data collected on an untextured sample) converged with R-F = 0.062 and
   R-wp = 0.175 (R-exp = 0.097). This structure is the first novel
   structure to be solved using the texture method in this configuration.
   As suggested by Si-29 MAS NMR results (1 Q(4) and 3 Q(3) signals, all
   of equal intensity), CAS-1 (C2, a = 24.158 &ANGS;, b = 7.016 &ANGS;, c
   = 6.482 &ANGS;, β = 95.19°) proved to be a layer silicate. The
   structure can be described as a series of silicate double layers
   connected via chains of edge-sharing CaO5(H2O) octahedra. There is a
   two-dimensional eight-ring channel system within the silicate layer,
   and K+ ions, which balance the charge, are located in the eight-rings
   of the two 4.8(2) nets that form the double layer. One water molecule
   is located in the channel system and another bridges between K+ and
   Ca2+ ions. The structure is related to that of the natural mineral

2005-38  ??

Anillo, A   Altomare, A   Moliterni, AGG   Bauer, EM   Bellitto, C
   Colapietro, M   Portalone, G   Righini, G
Hydrothermal synthesis, structural characterization and magnetic
   studies of the new pillared microporous ammonium Fe(III)
   carboxyethylphosphonate: [NH4][Fe-2(OH){O3P(CH2)(2)CO2}(2)]
The preparation by hydrothermal reaction and the crystal structure of
   the iron(III) carboxyethylphosphonate of formula
   [NH4][Fe-2(OH){O3P(CH2)(2)CO2}(2)] is reported. The green-yellow
   compound crystallizes in the monoclinic system, space group Pc(n.7),
   with the following unit-cell parameters: a = 7.193(3) A, b = 9.776(3)
   A, c = 10.17(4) A and beta = 94.3(2)degrees. It shows a typical layered
   hybrid organic-inorganic structure featuring an alternation of organic
   and inorganic layers along the a-axis of the unit cell. The
   bifunctional ligand [O3P(CH2)(2)CO2](3-) is deprotonated and acts as a
   linker between adjacent inorganic layers, to form pillars along the
   a-axis. The inorganic layers are made up of dinuclear Fe(III) units,
   formed by coordination of the metal ions with the oxygen atoms
   originating from the [O3P-](2-) end of the carboxyethylphosphonate
   molecules, the oxygen atoms of the [-CO2](-) end group of a ligand
   belonging to the adjacent layer and the oxygen atom of the bridged OH
   group. Each Fe(III) ion is six-coordinated in a very distorted
   octahedral environment. Within the dimer the Fe-Fe separation is found
   to be 3.5 A, and the angle inside the [Fe(1)-O(11)-Fe(2)] dimers is
   similar to124degrees. The resulting 3D framework contains micropores
   delimited by four adjacent dimers in the (bc) planes of the unit cell.
   These holes develop along the a-direction as tunnel-like pores and
   [NH4](+) cations are located there. The presence of the
   p-hydroxo-bridged [Fe(1)-O(11)-Fe(2)] dimers in the lattice is also
   responsible for the magnetic behavior of the compound at low
   temperatures. The compound contains Fe3+ ions in the high-spin state
   and the two Fe(III) ions are antiferromagnetic coupled. The J/k value
   of -16.3 K is similar to those found for other mu-hydroxo-bridged
   Fe(III) dimeric systems having the same geometry.


Muhle, C   Karpov, A   Jansen, M
Crystal structure elucidation of anhydrous Rb-2[Pt(CN)(4)] from X-ray
   powder diffraction data
The title compound has been synthesized by metathesis of
   Ba[Pt(CN)(4)].4 H2O with Rb2SO4, in aqueous solution. Its crystal
   structure was solved from X-ray powder diffraction data using the
   simulated-annealing approach, and refined by Rietveld's method. The
   compound crystallizes in space group Imma, a = 11.1432(2), b =
   7.4382(1), c = 11.1896(2) angstrom, V = 927.45(3) angstrom(3), Z = 4,
   R-P = 0.0402, R-W = 0.0247 (N-hkl = 173). Square-planar
   tetracyanoplatinate groups stack in an unprecedented eclipsed
   conformation, forming one-dimensional linear chains of Pt-atoms with
   Pt-Pt separations of 3.719 angstrom. Rb-2[Pt(CN)(4)] was characterized
   by differential thermal analysis, thermo-gravimetry and infrared


Ramirez-Cardona, M   Ventola, L   Calvet, T   Cuevas-Diarte, MA
   Rius, J   Amigo, JM   Reventos, MM
Crystal structure determination of 1-pentanol from low-temperature
   powder diffraction data by Patterson search methods
POWDER DIFFRACTION 20, 2005, 311-315.
In the course of our research on normal alkanols, the crystal structure
   of 1-pentanol has been solved by applying Patterson-search methods to
   laboratory powder X-ray diffraction data recorded on a curved
   position-sensitive detector (CPS120) at 183 K. The crystal structure
   was refined with the rigid-body Rietveld least-squares method. The cell
   is monoclinic, space group P2(1)/c, Z=4, and the cell parameters are a
   = 15.592(9) angstrom, b=4.349(1) angstrom, c=9.157(1) angstrom, beta =
   104.7(7)degrees, V=600.6(3) angstrom(3). There is one molecule in the
   asymmetric unit with the O-H bond in gauche conformation with respect
   to the alkyl skeleton. Packing is defined by the hydrogen bonds linking
   the 1-pentanol molecules along zigzag chains parallel to b.


Pan, ZG   Cheung, EY   Harris, KDM   Constable, EC   Housecroft, CE
Structural properties of methoxy derivatives of benzyl bromide,
   determined from powder X-ray diffraction data
POWDER DIFFRACTION 20, 2005, 345-352.
Structure determination of 3,5-dimethoxybenzyl bromide and
   3,4,5-trimethoxybenzyl bromide has been carried out from laboratory
   powder X-ray diffraction data using the direct-space Genetic Algorithm
   technique for structure solution followed by Rietveld refinement. These
   two compounds are of interest for their potential use as building
   blocks for the synthesis of dendritic materials. Although the two
   molecules differ only in the presence/absence of the methoxy group at
   the 4-position of the aromatic ring, the structural properties of the
   two materials are significantly different. (C) 2005 International
   Centre for Diffraction Data.


Grzechnik, A   Dmitriev, V   Weber, HP
Dilithium zirconium hexafluoride Li2ZrF6 at high pressures: A new
   monoclinic phase
Dilithium zirconium hexafluoride, Li2ZrF6 (P31m, Z = 1), is studied at
   high pressures using synchrotron angle-dispersive X-ray powder
   diffraction in a diamond anvil cell at room temperature. At atmospheric
   conditions, it has a structure with all the cations octahedrally
   coordinated to fluorine atoms. Above 10 GPa it transforms reversibly to
   a new polyrnorph (C2/c, Z = 4), in which the coordination polyhedron of
   the Zr atorns is a distorted square antiprism, while the Li atoms are
   in the octahedral coordination. The LiF6 octahedra form layers parallel
   to (100) that are connected by zig-zag chains of the edge-sharing Zr
   polyhedra running in the [001] direction. The relative change in
   volumes per one formula unit for both polymorphs is 6% at 11.8 GPa. The
   relations to other A(2)BX(6)-type structures are discussed.


Vila, E   Iglesias, JE   Galy, J   Castro, A
Synthesis and characterization of a novel bismuth-molybdenum oxide and
   study of its ionic conducting behavior
SOLID STATE SCIENCES 7, 2005, 1369-1376.
A wet chemistry method applied to the synthesis of bismuth-molybdenum
   oxides leads to the low temperature synthesis of a new phase with
   composition Bi10Mo3O24. The crystal data have been determined by ab
   initio indexing of the powder pattern. It crystallizes in the
   monoclinic system, with unit-cell parameters a = 23.7235(4), b =
   5.64720(8), c = 8.6798(1) angstrom, beta = 95.879(1)degrees and V =
   1156.73 angstrom(3). A preliminary heavy-atom skeleton related to the
   fluorite structure allowed us to postulate a layer structure with
   composition [Bi10O12](n) [MoO4](3n): This compound has been processed
   by spark plasma sintering as a ceramic material, exhibiting good ionic
   conductor properties in the whole temperature range of stability.


Blagden, N   Davey, R   Dent, G   Song, M   David, WIF
   Pulham, CR   Shankland, K
Woehler and Liebig revisited: A small molecule reveals its secrets -
   The crystal structure of the unstable polymorph of benzamide solved
   after 173 years
CRYSTAL GROWTH & DESIGN 5, 2005, 2218-2224.
In this work, we revisit the question of the metastable crystal form of
   benzamide. This was first identified in 1832 by Liebig and Woehler, but
   its structure has never been determined. It is shown how a combination
   of microscopic, spectroscopic, and diffraction techniques have been
   used to solve, finally, the structure of this highly metastable Form II
   of benzamide. The combination of morphology, disorder, and nucleation
   under highly labile conditions lead to some speculation as to the
   origins of such an unstable polymorph.


David, WIF   Shankland, K   Pulham, CR   Blagden, N   Davey, RJ   Song, M
Polymorphism in benzamide


Surble, S   Serre, C   Millange, F   Pelle, F   Ferey, G
Synthesis, characterisation and properties of a new three-dimensional
   Yttrium-Europium coordination polymer
SOLID STATE SCIENCES 7, 2005, 1074-1082.
A new three-dimensional europium-doped Yttrium(III) tricarboxylate,
   MIL-92LT(1) or Y1-xEux (H2O)(2) {C6H3-(CO2)(3)} (x similar to 0.03)
   (LT: Low Temperature) has been synthesised hydrothermally. Its
   three-dimensional structure, determined using X-ray powder diffraction
   data, is built-up from isolated eight coordinated Ln(III) monocapped
   square antiprisms (Ln = Y, Eu) linked through carboxylate moieties. Its
   thermal behaviour, investigated using TGA and X-ray
   thermodiffractometry indicates that dehydration is irreversible giving
   the solid MIL-92(HT) or Y1-xEux {C6H3-(CO2)(3)} (x similar to 0.03)
   (HT: High Temperature). It induces a change in the connection mode of
   the carboxylate and a decrease in the coordination number of the
   rare-earth leading to an unusual octahedral environment for the
   rare-earth cation. After a structural analysis of the reconstructive
   phase transition, the optical properties of these solids have been
   investigated and show that dehydration leads to a strong increase in
   the optical output. Crystal data for MIL-92(LT): monoclinic space group
   C2/c (n degrees 15) with a = 16.428 (1) angstrom, b = 6.071 (1)
   angstrom, c = 20.404(l) angstrom, beta = 95.31(3)degrees and Z = 2.
   Crystal data for MIL-92(HT): monoclinic space group C2/c (n degrees 15)
   with a = 17.390(1) angstrom, b = 5.521 (1) angstrom, c = 19.487(1)
   angstrom, beta = 105.35 (2)degrees and Z = 2.


Harper, JK   Barich, DH   Heider, EM   Grant, DM   Franke, RR
   Johnson, JH   Zhang, YG   Lee, PL   Von Dreele, RB   Scott, B
   Williams, D   Ansell, GB
A combined solid-state NMR and X-ray powder diffraction study of a
   stable polymorph of paclitaxel
CRYSTAL GROWTH & DESIGN 5, 2005, 1737-1742.
Solid-state NMR (SSNMR) and X-ray powder diffraction (XRPD) allow a
   study of a novel and stable polymorph of paclitaxel (Taxol) with two
   molecules per asymmetric unit (Z') in the P2(1)2(1)2(1) space group.
   The asymmetric unit volume is 2167 angstrom(3), about four times larger
   than that previously characterized in combined XRPD/ SSNMR studies. The
   method, employing SSNMR constraints, allows the XRPD Rietveld analysis
   to establish many of the lattice details that otherwise would be
   unavailable. NMR structural constraints are provided by isotropic
   shifts and three-dimensional (3D) chemical shift tensors (CST), which
   are determined by ab initio quantum mechanical calculations. CST data
   give highly sensitive information on short-range structural features
   such as intra-atomic distances (particularly for proton positions that
   are undetermined with XRPD methods) and short-range valence angles that
   exhibit relatively poor sensitivity in reasonably large
   microcrystalline powders. Conversely, space group symmetry, unit cell
   volumes, long-range cell dimensions, and dihedral angles of extended
   chains are estimated with XRPD measurements. Corroboration of many
   structural parameters by combined quantum mechanical, SSNMR, and XRPD
   results indicate the efficacy of these combined approaches in
   relatively sizable microcrystalline powders. The population of the
   asymmetric unit, Z' = 2 is clearly observed even in the one-dimensional
   isotropic C-13 spectra, which also confirmed the stability of the
   polymorph over a three-year period. This structural determination
   depends specifically on the agreement between previous SSNMR CSTs and
   single crystal results for baccatin, the rigid part of paclitaxel.
   Hence, CST data provide a reasonable initial model for the early
   iterative steps of a Rietveld analysis of XRPD data for a new polymorph
   of Taxol.


Wu, L   Chen, XL   Li, H   He, M   Xu, YP   Li, XZ
Structure determination and relative properties of novel cubic borates
   MM '(4)(BO3)(3) (M = Li, M ' = Sr; M = Na, M ' = Sr, Ba)
INORGANIC CHEMISTRY 44, 2005, 6409-6414.
A series of novel borates, MM'(4)(BO3)(3) (M = Li, M' = Sr; M = Na, M'
   = Sir, Ba), have been successfully synthesized by standard solid-state
   reaction. The crystal structures have been determined from powder X-ray
   diffraction data. They crystallize in the cubic space group laid with
   large lattice parameters: a = 14.95066(5) angstrom for LiSr4(BO3)(3), a
   = 15.14629(6) angstrom for NaSr4(BO3)(3), and a = 15.80719(8) angstrom
   for NaBa4(BO3)(3). The structure was built up from 64 small cubic
   grids, in which the M' atoms took up the corner angle and the BO3
   triangles or MO6 cubic octahedra filled in the interspaces. The
   isolated [BO3](3-) anionic groups are perpendicular to each other,
   distributed along three (100) directions. The anisotropic polarizations
   were counteracting, forming an isotropic crystal. Sr and Ba atoms were
   found to be completely soluble in the solid solution
   NaSr4-xBax(BO3)(3)(0 <= x <= 4). The photoluminescence of samples doped
   with the ions Eu2+ and Eu3+ was studied, and effective yellow and red
   emission was detected, respectively, The results are consistent with
   the crystallographic study. The! DTA and TGA curves of them show that
   they are chemically stable and congruent melting compounds.


Florence, A   Johnston, A   Fernandes, P   Shankland, K
   Stevens, HNE   Osmundsen, S   Mullen, AB
Powder study of hydrochlorothiazide form II
The crystal structure of hydrochlorothiazide form II, C7H8ClN3O4S2, was
   solved by simulated annealing from laboratory X-ray powder diffraction
   data collected at room temperature to 1.76 angstrom resolution.
   Subsequent Rietveld refinement yielded an R-wp of 0.0376 to 1.49
   angstrom resolution. The molecules crystallize in the space group
   P2(1)/c with one molecule in the asymmetric unit. The structure is
   stabilized by three N-H (. . .) N and one N-H (. . .) O hydrogen-bonded
   intermolecular interaction.


Florence, AJ   Johnston, A   Shankland, K
Powder study of hydrochlorothiazide-methyl acetate (1/1)
A polycrystalline sample of the title compound,
   C(7)H(8)ClN(3)O(4)S(2) .  C3H6O2, was produced during an
   automated parallel crystallization search on hydrochlorothiazide (HCT).
   The crystal structure was solved by simulated annealing from laboratory
   X-ray powder diffraction data collected at room temperature to 1.75
   angstrom resolution. Subsequent Rietveld refinement yielded an R-wp
   value of 0.0182 to 1.54 angstrom resolution. The compound crystallizes
   with one molecule of HCT and one of methyl acetate in the asymmetric
   unit and displays an extensive hydrogen-bonding network.


Banerjee, S    Mukherjee, AK   Banerjee, I   De, RL   Neumann, MA   Louer, D
Synthesis, spectroscopic studies and ab-initio structure determination
   from X-ray powder diffraction of
The synthesis, spectroscopic studies and crystal structure
   determination from X-ray powder diffraction have been carried out for
   bis-(N-3-acetophenylsalicylaldiminato)copper(II). The structure is
   triclinic, space group P (l) over bar with unit cell dimensions
   a=11.817(1)angstrom, b=12.087(1)angstrom, c=9.210(1)A,
   alpha=102.62(1)degrees, beta=111.16(1)degrees, gamma=86.15(1)degrees,
   V=1197.0(2)angstrom(3), Z=2. The structure has been solved by Monte
   Carlo simulated annealing approach and refined by GSAS package. The
   final Rp value was 8.68%. The coordination geometry around the copper
   atom in the complex is intermediate between square-planar and
   tetrahedral with two salicylaldimine ligands in trans arrangement.
   Intermolecular C-(HO)-O-.... hydrogen bonds between molecules related
   by translation generate infinite chains along [010] direction. The
   molecular chains are linked via additional C-(HO)-O-.... hydrogen bonds
   to form a three-dimensional supramolecular network.


Zhang, LM   Schneider, J   Luck, R
Phase transformations and phase stability of the AlCuFe alloys with
   low-Fe content
INTERMETALLICS 13, 2005, 1195-1206.
Phase transformation and microstructure of the AlCuFe alloys of the
   approximate compositional range of 20-50 at.% Cu and 1-10 Fe at.% have
   been investigated for annealed samples by means of differential thermal
   analysis, magneto-thermal analysis, scanning electron microscopy,
   electron probe analysis and powder X-ray diffraction. Representative
   phase transformations categorized as polymorphic, discontinuous
   precipitation, quasi-binary eutectoid, and ternary transition reaction
   (U-type) phase transformation are presented. These phase
   transformations are found to have a common feature, which is
   characterized by a dissolution of a primitive CsCl-type cubic phase and
   a formation of a face-centered orthorhombic phase. The crystal
   structures of the cubic and orthorhombic phases are determined from the
   powder diffraction data using routines for indexing DICVOL, for
   intensity extraction and ab initio structure determination EXPO and for
   Rietveld refinement FULPROF. A face-centered orthorhombic cell (a =
   8.1530(3), b = 14.1370(4), c = 10.0736(4), Vol = 1161.0(7), Z = 4, at
   room temperature) with a starting structural model of,zeta-Al3Cu4
   (space group Fmm2, Z=4) approximates the observed pattern of powder
   sample quenched from 620 degrees C fairly well. Refined orthorhombic
   cell dimensions are obtained by in situ high-temperature X-ray
   diffraction at 463, 553 and 636 degrees C. These phase transformations
   are sensitive to the heat treatment and the alloy composition. They can
   be suppressed at moderate cooling rates. The metastable structures for
   both slowly cooled and as-cast alloys are found to contain the cubic
   phase replacing the equilibrium orthorhombic phase.


Littner, A   Francois, M   Tobola, J   Elkaim, E   Malaman, B   Vilasi, M
Ab-initio crystal structure of Mo4+xRu9-xSi5 (0 <= x <= 1) by
   synchrotron powder diffraction and electronic properties calculation
   (KKR method)
INTERMETALLICS 13, 2005, 1048-1055
The crystal structure of the new phase Mo26Ru47Si27 (beta phase)
   discovered during the study of the Mo-Ru-Si phase diagram performed in
   the aim of finding materials for high temperature applications, was
   determined by ab-initio methods from powder synchrotron diffraction
   data. Distribution of Ru and Mo atoms in the structure is specified by
   total energy electronic structure calculations using
   Korringa-Kohn-Rostoker method. The compound crystallizes in P4/mmm
   space group with a=9.2164(1) angstrom, c=2.88721(1), angstrom, D-x =
   9.69(1) g/cm(3). The structure has been refined by the Rietveld method
   down to R-p = 1.1%, R-B = 12.0%, R-F = 8.7% for 6814 observed data and
   271 independent reflections. The structure consists of four distorted
   cubes 'Mo4Si4' centered by Ru atoms, sharing edges in the (a,b) planes
   to form cross-like units linked each others by the lateral faces of the
   branches in the (a,b) planes and stacked by faces along the c
   direction. The center of the crosses is occupied by Mo or Ru atoms
   (disorder 1d site) in an octahedral coordination. The spacing between
   the connected crosses is filled by four others distorted cubic units
   'Mo4Si4' centered themselves by Ru atoms.
   The composition of the beta phase, determined by microprobe analysis,
   presents an homogeneity domain, which can be expressed by the unit
   formula Mo4+xRu9-xSi5 (0 <= x <= 1) compatible with a partial or fully
   occupation by Mo or Ru of the Wyckoff position Id of the structure.
   Electronic properties of ordered and disordered models of Mo4+xRu9-xSi5
   are also discussed.

2005-54  ??

Rousse, G   Klotz, S   Saitta, AM   Rodriguez-Carvajal, J
   McMahon, MI   Couzinet, B   Mezouar, M
Structure of the intermediate phase of PbTe at high pressure
PHYSICAL REVIEW B 71, 2005, 224116
The evolution of PbTe with pressure has been reexamined using
   synchrotron x-ray diffraction. The phase transition at 6 GPa is not to
   the GeS (B16) or TII (B33) type structures, as previously reported, but
   to an orthorhombic Pnma structure, with cell parameters a=8.157(1),
   b=4.492(1), and c=6.294(1)A at 6.7 GPa. This structure corresponds to a
   distortion of the low-pressure NaCl structure with a coordination
   intermediate between the sixfold B1 (NaCl) and the eightfold B2 (CsCl)
   structure. We discuss the stability of this new structure with respect
   to other proposed phases using numerical methods. These results may
   modify the admitted paths of phase transitions between the B1 and B2


Loiseau, T   Muguerra, H   Haouas, M   Taulelle, F   Ferey, G
Hydrothermal synthesis and structural characterization of a gallium
   pyromellitate Ga(OH)(btec) .  0.5H(2)O, with infinite
   Ga-(mu(2)-OH)Ga chains (MIL-61)
SOLID STATE SCIENCES 7, 2005, 603-609
A new gallium carboxylate Ga(OH)(btec) .  0.5H(2)O (MIL-61) was
   synthesized under mild hydrothermal conditions (200 degrees C, 24
   hours) in the presence of 1,2,4,5-benzenetetracarboxylic (btec) acid
   and water. The crystal structure, characterized by means of Rietveld
   refinement of powder XRD data, consists of trans chains of GaO4(OH)(2)
   octahedra, connected to each other through a mu(2)-OH group. The
   three-dimensional framework is built up from these chains linked
   together via the organic molecules so delimiting the cavities where the
   water molecules are encapsulated. Analysis by solid state NMR (1 H and
   C-13) has confirmed the presence within the structure of both water
   molecules and carboxylate moieties partially deprotonated. The
   structure of Ga(OH)(btec) .  0.5H(2)O corresponds to that of
   MIL-61 obtained with vanadium replacing gallium.
   Crystal data for Ga-4(OH)(4)((HO2C)(2)-C6H4-(CO2)(2))(4) .
   2H(2)O: a = 14.8325(10) angstrom, b = 6.7792(10) angstrom, c =
   10.6726(10) angstrom, V 1073.2(2) angstrom(3), Prima (n degrees 62).


van der Lee, A   Richez, P   Tapiero, C
Crystal structure of nitarsone determined from synchrotron X-ray powder
   diffraction data
The crystal structure of nitarsone, 4-nitrophenylarsonic acid, a
   substitute for nifursol and dimetridazole in the prevention and
   treatment of turkey histomoniasis desease, has been determined from
   synchrotron X-ray powder diffraction data. Nitarsone crystallizes in
   the monoclinic space group P2(1)/n with unit cell parameters a =
   7.46413(5), b = 25.68543(17), c = 4.657388(32) &ANGS;, &beta; =
   105.4670(5)&DEG;. The structure was solved using simulated annealing
   techniques by treating the molecule as a rigid body for which the
   configuration resulting from an energy minimization was used in
   slightly adapted form, Structure refinement treated the NO2 and the
   AsO(OH)(2) groups as free groups, leading to final confidence factors
   R-p = 0.059 and R-wp = 0.071. The crystal structure contains 4
   molecules per unit cell that are hydrogen bonded to form infinite
   chains of dimers running along the c-axis. Nitarsone's low toxicity
   when compared with inorganic sources of arsenic is explained by the
   existence of a partial double C-As bond (1.866(5) &ANGS;) which confers
   greater stability so that under physiological conditions nitarsone is
   not converted to mineral-like As V or III.


Guo, F   Harris, KDM
Structural understanding of a molecular material that is accessed only
   by a solid-state desolvation process: The scope of modern powder X-ray
   diffraction techniques


Papoular, RJ   Allouchi, H   Chagnes, A   Dzyabchenko, A   Carre, B
   Lemordant, D   Agafonov, V
X-ray powder diffraction structure determination of gamma-butyrolactone
   at 180 K: phase-problem solution from the lattice energy minimization
   with two independent molecules
The crystal structure of the solid phase of the dipolar aprotic solvent
   &gamma;-butyrolactone (BL1), C4H6O2, has been solved using the
   atom-atom potential method and Rietveld-refined against powder
   diffraction data collected at T = 180 K with a curved
   position-sensitive detector (INEL CPS120) using Debye-Scherrer
   diffraction geometry with monochromatic X-rays. It was first deduced
   from the X-ray experiment that the lattice parameters are a = 10.1282
   (4), b = 10.2303 (5), c = 8.3133 (4) &ANGS;, &beta; = 93.291 (2)&DEG;
   and that the space group is P2(1)/a, with Z = 8 and two independent
   molecules in the asymmetric unit. The structure was then solved by
   global energy minimization of the crystal-lattice atom-atom potentials.
   The subsequent GSAS-based Rietveld refinement converged to the final
   crystal-structure model indicator R-F2 = 0.0684, profile factors R-p =
   0.0517 and R-wp = 0.0694, and a reduced &chi;(2) = 1.671. After further
   cycles of heating and cooling, a powder diffraction pattern markedly
   different from the first pattern was obtained, again at T = 180 K,
   which we tentatively assign to a second polymorph (BL2). All the
   observed diffraction peaks are well indexed by a triclinic unit cell
   essentially featuring a doubling of the a axis. An excellent Le Bail
   fit is obtained, for which R-p = 0.0312 and R-wp = 0.0511.


Loiseau, T   Mellot-Draznieks, C   Muguerra, H   Ferey, G
   Haouas, M   Taulelle, F
Hydrothermal synthesis and crystal structure of a new three-dimensional
   aluminum-organic framework MIL-69 with 2,6-naphthalenedicarboxylate
   (ndc), Al(OH)(ndc) .  H2O
COMPTES RENDUS CHIMIE 8, 2005, 765-772.
A new three-dimensional aluminum-organic framework, MIL-69 or
   Al(OH)(O2C-C10H6-CO2)(H2O)-H-., has been hydrothermally synthesized at
   210 &DEG; C for 16 h, by using 2,6-naphthalenedicarboxylic acid as a
   rigid ligand. The model for the crystal structure of MIL-69 was
   determined by means of lattice energy minimizations and further refined
   against the powder XRD data using the Rietveld refinement method. The
   crystal structure consists of infinite chains of AlO4(OH)(2) octahedra
   corner-linked through the &mu;(2)-hydroxyl groups and connected by the
   2,6-naphthalenedicarboxylate moieties. It results in the formation of
   flat channels parallel to the chains of aluminum octahedra, running
   along the c axis. A water molecule is trapped nearby the center of the
   tunnels and mainly interacts via hydrogen bonds with the hydroxyl
   groups and the oxygen atoms of the carboxylates. Although the
   three-dimensional aluminum-organic framework is stable up to 450 &DEG;
   C, the tunnels still remain shrunk upon removal of water molecule,
   because of the occurrence 7r-n interactions between the naphthalene
   groups. The MIL-69 phase was characterized by solid state NMR
   MAS(27)Al, H-1 and C-13{H-1-decoupled}, which is consistent with the
   crystal structure description. Crystal data. - MIL-69,
   Al(OH)(O2C-C10H6-CO2)(H2O)-H-.: Mr = 267.11 g mol(-1), monoclinic,
   space group C2/c (no. 15), a = 24.598(2) &ANGS;, b = 7.5305(6) &ANGS;,
   c = 6.5472(5) &ANGS;, &beta; = 106.863(8)&DEG;, V = 1160.6(2)
   &ANGS;(3), Z = 4.


Fernandes, P   Florence, A   Shankland, K   David, WIF
Powder diffraction study of 1,2 : 3,4-dibenzanthracene
The crystal structure of 1,2:3,4-dibenzanthracene, C22H14, was solved
   by simulated annealing from laboratory X-ray powder diffraction data
   collected at room temperature to 1.8 &ANGS; resolution. Subsequent
   Rietveld refinement yielded an R-wp value of 0.036. The molecules
   crystallize in space group P2(1) with two independent molecules in the
   asymmetric unit which pack in a stacked arrangement along the b axis.


Lewis, GR   Steele, G   McBride, L   Florence, AJ   Kennedy, AR
   Shankland, N   David, WIF   Shankland, K   Teat, SJ
Hydrophobic vs. hydrophilic: Ionic competition in remacemide salt
CRYSTAL GROWTH & DESIGN 5, 2005, 427-438.
Remacemide [2-aniino-N-(1-methyl-1,2-diphenylethyl)-acetamide] was
   developed as a potential antagonist for epilepsy, Parkinsonism, and
   Huntington's disease. This paper investigates hydrophilic and
   hydrophobic intermolecular interactions that occur within the series of
   crystal structures comprising remacemide 1 and six of its salts [2 =
   chloride; 3 = nitrate; 4 = acetate (C2H3O2-); 5 = hydrogenfumarate
   (C4H3O4-); 6 = naphthalene-2-sulfonate (napsilate, C10H7O3S-); 7 =
   1-hydroxynaphthalene-2-carboxylate (xinafoate, C11H7O3-)]. The
   hydrophilic interactions are described through graph set analyses of
   the hydrogen bond motifs and networks. The lattice of 1 comprises
   unidirectional, one-dimensional chains of molecules parallel to the
   c-axis. In 2, the cation-anion hydrogen bonding imposes a well-defined
   hydrophilic stratum structure on the lattice. As the cation itself is
   amphiphilic, a natural consequence of this is the creation of
   two-dimensional stacked layers with alternating hydrophilic and
   hydrophobic character (lattice bilayers). This tendency to form
   bilayers within the lattice is also observed in structures 3-5 (polar
   anions) and structures 6-7 (amphiphilic anions). Relatively few
   well-directed intermolecular interactions are observed between aromatic
   rings, either in 1 or in the hydrophobic layers of 2-7. Therefore, it
   is concluded that it is the hydrophilic hydrogen bond interactions that
   dominate the crystal packing and drive the segregation into lattice
   bilayers in the salt crystal structures.


Bhuvanesh, NSP   Reibenspies, JH   Golden, ML   Darensbourg, MY
   Zhang, YG   Lee, PL
The vapochromic behavior, desulfoxidation and structural
   characterization of the SO2 adducts of Ni(BME-DACH) from powder data
   CHEMISTRY 35, 2005, 11-17.
Ab-initio structure determination of Ni(BME-DACH). SO2 has been carried
   out by a combination of real space methods and Rietveld analysis from
   powder X-ray diffraction patterns obtained from microgram quantities of
   the compound mounted on a nylon loop (space group. P2(1)/c, a =
   8.871(1), b = 14.480(1), c = 10.576(1) angstrom, beta =
   95.98(1)degrees. The structure of Ni(BME-DACH). SO2 shows that
   Ni(BME-DACH) complex remains intact and is related to the structure of
   Ni(BME-DACH).2SO(2), providing a platform for SO2 binding. We have also
   followed the desulfoxidation of the 2SO(2) adduct by in-situ
   micro-powder X-ray diffraction and, based on the results, a mechanism
   is proposed.


Janaswamy, S   Chandrasekaran, R
Polysaccharide structures from powder diffraction data: molecular
   models of arabinan
CARBOHYDRATE RESEARCH 340, 2005, 835-839.
X-ray intensity data from a polycrystalline sample of debranched
   arabinan, [-> 5)-alpha-L-Ara(f)-(1 ->](n), have been obtained using a
   powder diffractometer in order to determine its three-dimensional
   structure. The observed peaks index on a monoclinic cell with a =
   5.444(7), b = 6.395(10), c = 8.680(5) angstrom, and gamma =
   99.6(3)degrees, V = 298 angstrom(3). One 2-fold helix along the c-axis
   can be accommodated in the unit cell. Molecular and packing models have
   been analyzed using the seven C-2'-endo/C-3'-endo allomorphs originally
   proposed by Radha and Chandrasekaran [Carbohydr. Res. 1997, 298, 105].
   The generated powder pattern matches closely with the observed
   diffraction only for one C-2'-endo model. In this structure, the three
   main chain conformation angles are in the trans domains, there are no
   intra-chain hydrogen bonds, and the packing arrangement is stabilized
   by inter-chain O-3-(HO)-O-...-2 bonds.


Yuan, WX   Hu, JW   Song, YT   Wang, WJ   Xu, YP
Synthesis and structure of the ternary nitride Li6WN4
POWDER DIFFRACTION 20, 2005, 18-21.
The ternary nitridotungstate Li6WN4 has been synthesized via the solid
   state reaction of lithium subnitride, Li3N, with W under nitrogen. High
   quality X-ray powder diffraction data were collected for the
   crystal-structure determination. Li6WN4 crystallizes in the tetragonal
   system, space group P4(2)/nmc, with cell parameters a = 6.6759(3)
   angstrom and c = 4.9280(3) angstrom, Z = 2. Preliminary thermal
   stability measurements of Li6WN4 show that it is sensitive to moisture,
   even at room temperature, and decomposes at high temperatures below
   1000 degrees C under flowing nitrogen.


Hofmann, K   Albert, B
Crystal structures of M-2[B10H10] (M = Na, K, Rb) via real-space
   simulated annealing powder techniques
Alkali metal decahydro-closo-decaborates M-2[B10H10] (M = Na, K, Rb)
   were synthesised by ion-exchange and characterised via infrared and
   B-11-NMR spectroscopy. The crystal structures of Na-2[B10H10,],
   K-2[B10H10], and Rb-2[B10H10] were determined from X-ray powder
   diffraction data using real-space techniques. The compounds crystallise
   in the monoclinic space group P2(1)/n (no. 14) with the lattice
   constants: Na2[B10H10]: a = 1028.28(6) pm, b = 1302.18(5) pm, c =
   667.34(3) pm, beta = 93.754(3)degrees; K-2[B10H10]: a = 1285.54(8) pm,
   b = 1117.84(7) pm, c = 682.27(4) pm, beta = 93.357(3)degrees;
   Rb-2[B10H10]: a = 1320.04(7) pm, b = 1136.88(6) pm, c = 704.23(4) pm, P
   = 94.158(3)degrees. The hydroborate anions are arranged almost
   hexagonally with alkali metal cations in the tetrahedral interstices.


Chui, SSY   Ng, MFY   Che, CM
Structure determination of homoleptic Au-I, Ag-I, and Cu-I
   aryl/alkylethynyl coordination polymers by X-ray powder diffraction
This article describes the structure determination of five homoleptic
   d(10) metal-aryl/alkylacetylides [RC equivalent to CM] (M=Cu, R=tBu 1,
   nPr 2, Ph 3; R = Ph, M = Ag 4; Au 5) by using X-ray single-crystal and
   powder diffraction. Complex 1(.)C(6)H(6) reveals an unusual Cu-20
   catenane cluster structure that has various types of tBuC equivalent to
   C -> Cu coordination modes. By using this single-crystal structure as a
   starting model for subsequent Rietveld refinement of X-ray powder
   diffraction data, the structure of the powder synthesized from CuI and
   tBuC equivalent to CH was found to have the same structure as 1.
   Complex 2 has an extended sheet structure consisting of discrete
   zig-zag Cu-4 subunits connected through bridging nPrC equivalent to C
   groups. Complex 3 forms an infinite chain structure with extended Cu-Cu
   ladders (Cu-Cu = 2.49(4)-2.83 (2) angstrom). The silver(I) congener 4
   is iso-structural to 3 (average Ag-Ag distance 3.11 angstrom), whereas
   the gold(I) analogue 5 forms a (AuAu)-Au-... honeycomb network with PhC
   equivalent to C pillars (Au-Au = 2.98(1)-3.26(1) angstrom). Solid-state
   properties including photoluminescence, v(C equivalent to C) stretching
   frequencies and thermal stability of these polymeric systems are
   discussed in the context of the determined structures.


Stock, N   Guillou, N   Senker, J   Ferey, G   Bein, T
Synthesis and characterization of the tetraphosphonic acid ester
   (Et2O3PCH2)(4)C6H2 and the open-framework cadmium tetraphosphonate,
Following the strategy of using polyfunctional phosphonic acids for the
   synthesis of open-framework metal phosphonates, the ethyl ester of a
   tetraphosphonic acid, i. e. (Et2O3PCH2)(4)C6H2 (1) was synthesized and
   used in the hydrothermal synthesis of the new cadmium tetraphosphonate,
   Cd-2[(HO3PCH2)(4)C6H2] (2). The structure of 1 was solved from single
   crystal data (1: triclinic, P (1) over bar, a 12.3846(2), b =
   12.6166(3), c 12.9915(3) Angstrom, alpha = 86.380(1), beta = 63.372(1),
   gamma = 89.589(1)degrees, V = 1810.51(7) Angstrom3, Z = 2, R1 = 0.077,
   wR2 = 0.177). The in situ hydrolysis of the ethyl ester and the
   reaction with the Cd2+ ions leads to the well-crystallized
   microcrystalline product 2. Its structure was solved and refined using
   X-ray powder diffraction data (2: triclinic, P (1) over bar, with a =
   11.0435(5), b = 7.5809(3), c = 5.4250(2) Angstrom, alpha = 98.354(2),
   beta = 101.951(2), gamma = 95.885(3)degrees, V = 435.48(9) Angstrom3, Z
   = 1, R(w)p = 0.096, R-P = 0.072, R-B = 0.081, R-F = 0.069). Whereas the
   structure of I is a molecular structure, the structure of
   Cd-2[(HO3PCH2)(4)C6H2] (2) is built up from edge sharing CdO6 octahedra
   forming dimeric [Cd2O10] polyhedra. In the second coordination sphere
   of each of the Cd-II ions six HO3PCH2R units are observed. The [Cd2O10]
   polyhedra are connected to six other [Cd2O10] polyhedra by ten
   hydrogenphosphonic acid units. Thus inorganic sheets are formed that
   are connected to a three-dimensional framework with small channels,
   through the phenyl rings. Thermogravimetric as well as IR-,
   Cd-13-MAS-NMR and P-31-MAS-NMR data are also presented.


Abdelouhab, S   Francois, M   Elkaim, E   Rabu, P
Ab initio crystal structure of copper(II) hydroxy-terephthalate by
   synchrotron powder diffraction and magnetic properties
SOLID STATE SCIENCES 7, 2005, 227-232.
The structure of Cu-2(OH)(2)(C8H4O4) has been determined by ab initio
   XRPD methods from synchrotron data. The compound crystallizes in P-1
   space group, a = 10.1423(4) Angstrom, b = 6.3388(2) Angstrom, alpha =
   3.4841(1) Angstrom, alpha = 99.170(2)degrees, beta = 96.567(2)degrees,
   gamma = 98.760(3)degrees, D-x = 2.497 g cm(-3). The structure has been
   fully refined by the Rietveld method down to R-p = 0.077 for 9651
   observed data points (513 reflections of which 193 are independent).
   The structure consists of layered hydroxides Cu(OH)(2) intercalated by
   terephthalate anions, at the interlayer space forming a 3D framework
   similar to Co(II)-based compound. The apticity of the tp anion and the
   octahedral coordination of the metal ions are similar in both compounds
   and can be formulated as M-2(mu(3)-OH)(2)(A(6)-eta(1), eta(2), eta(1),
   eta(2)-tp) with M = Cu and Co. Although Cu(II)-based structure is very
   similar to the monoclinic (C2/m) Co(II)-based analogue, the former is
   completely ordered in contrast with the later which is disordered. The
   lower symmetry in Cu(II)-based compound due to the Jahn-Teller effects
   inducing an elongation of the octahedrons CuO6 with four short
   distances of about 2.0 Angstrom and two long distances Cu-O up to 2.8
   Angstrom is also observed to be different from Co(II)-based compound.
   Whereas the Co(II) derivative exhibits noncollinear antiferromagnetic
   coupling between the ferrimagnetic hydroxide layers, the magnetic
   behavior of the copper(II) analogue indicate a ferromagnetic coupling
   through the terephthalate bridge between ferromagnetic sheets with
   in-plane interaction J = +5.5 K.


Vanhoyland, G   Pagnaer, J   D'Haen, J   Mullens, S   Mullens, J
Characterization and structural study of lanthanum citrate trihydrate
   [La(C6H5O7)(H2O)(2)] .  H2O
[La(C6H5O7)(H2O)(2)] (.) H2O was synthesized as precursor material for
   an aqueous solution-get route to La-containing multimetal oxides. The
   compound was characterized by means of FTIR, TGA and pycnometry. The
   crystallographic structure was solved from powder diffraction data. The
   symmetry is monoclinic [a = 17.097(3) Angstrom, b = 9.765(2) Angstrom,
   c = 6.3166(8) Angstrom and beta = 90.42(1)degrees, Z(exp) = 3.96] with
   space group P2(1)/n (14). Direct methods were applied and the model was
   subsequently least-squares refined (R-B 5.1 % and R-wP = 12.0%). La3+
   is nine-fold coordinated, the LaO9 forming a mono-capped square
   antiprism. The basic unit is a binuclear entity of two LaO9 polyhedra
   having one edge in common. These units are connected along the c-axis
   through citrate molecules. The carboxylate groups of the citrate are
   coordinated to La3+ in monodentate, bidentate and bridging way. Also
   the alkoxide group, which carries the proton, is coordinated to La3+.
   Two water molecules complete the coordination sphere, while the third
   one can be found inbetween the La3+ -citrate network.


Josse, M   Dubois, M   El-Ghozzi, M   Cellier, J   Avignant, D
Anti-KSbF6 structure of CaTbF6 and CdTbF6: a confirmation of the
   singular crystal chemistry of Tb4+ in flourides
The crystal structures of two new tetravalent terbium fluorides, CaTbF6
   (and CdTbF)(, have been determined from X-ray and neutron powder
   diffraction data. The title compounds exhibit an anti-KSbF)(6)(6)
   (structure, the three-dimensional framework of which is built of
   [TbF)(]2- chains of edge-sharing dodecahedra further linked, by sharing
   corners, to isolated [MF)(]4- octahedra (M = Ca, Cd). The mechanism of
   the anionic sublattice rearrangement when going from KSbF)(6)(6)(6) (to
   CaTbF)(6) (is described and related to a simple cubic fluoride-ion
   packing. Comparison with the crystal structures of b-BaTbF)(6) (and
   other representatives of the MII MIVF)(6) family allows the singular
   crystal-chemical properties of some fluoroterbates to be emphasized.


Mora, AJ   Avila, EE   Delgado, GE   Fitch, AN   Brunelli, M
Temperature effects on the hydrogen-bond patterns in
   4-piperidinecarboxylic acid
A temperature-controlled X-ray powder diffraction experiment,
   complemented with TGA and DSC analysis, allowed us to follow changes in
   the molecular conformation and hydrogen-bond patterns of
   4-piperidinecarboxylic acid. The presence of three phases is confirmed.
   Phase 1 represents the monohydrated form of 4-piperidinecarboxylic
   acid, which exists from room temperature to 359 K, where dehydration
   occurs. Phase 2 measured at 363 K corresponds to an anhydrous form of
   the acid. At ca 458 K the onset of a second, more gradual transition is
   observed, which ends at around 543 K. Phase 3 measured at 543 K is a
   high-temperature anhydrous form of the acid. The structures of phases 2
   and 3 were solved from synchrotron powder diffraction data by simulated
   annealing using the DASH program and refined by the Rietveld method.
   The phase changes are accompanied by modification of the hydrogen-bond
   patterns and of the torsional orientation of the terminal carboxylate
   group. This group makes a 49degrees rotation about the C1 - C2 bond
   during the first transition.


Casellas, H   Costantino, F   Mandonnet, A   Caneschi, A   Gatteschi, D
X-ray powder and single crystal structures of two unprecedented
   families of bpca-based 1-D magnetic chains (Hbpca =
INORGANICA CHIMICA ACTA 358, 2005, 177-185.
Two unprecedented families of bpca-based mono-dimensional complexes
   Cu(bpca)(X) (X = CN, 1; N-3, 2) and [Cu1-xFex(bpca)](ClO4) (X = 0, 3;
   0.23, 4) were synthesised. The structure of I was solved ab initio from
   X-ray powder diffraction data and refined by Rietveld methods. The
   complexes 3-4 were characterised by X-ray single crystal diffraction.
   In I the cyano ligand coordinates the metal centres, the Cu centres
   forming a zigzag 1-D chain along the (0 0 1) direction, while in 3-4,
   the bpca ligand itself acts as the link towards the metal ions which
   are arranged in a linear 1-D chain running parallel to the (0 0 1)
   direction. An infrared spectroscopy study confirmed these coordination
   modes. The magnetic properties of both chain families were studied. 1-2
   do not show significant magnetic interactions, whereas the magnetic
   behaviour for 3-4 suggests dominant antiferromagnetic interactions
   between the metal ions within the chains. The magnetic behaviour of 3
   was analysed using the Pade approximation of the Bonner-Fisher model
   for S = 1/2 antiferromagnetic chains. The J value was estimated as 10

2005-73 ???

Pitt, MP   Blanchard, D   Hauback, BC   Fjellvag, H   Marshall, WG
Pressure-induced phase transitions of the LiAlD4 system
PHYSICAL REVIEW B 72, 2005, 214113
Compression of the LiAlD4 system has been studied using in situ
   time-of-flight neutron diffraction up to 7.15 GPa and 60 degrees C. At
   ambient temperature (T-a), the structure remains as monoclinic
   alpha-LiAlD4 up to 7.05 GPa, displaying a 26.9% reduction in unit cell
   volume to 200.9 angstrom(3), yielding a 28.7% increase in volumetric
   efficiency to 136.5 kg D-2/m(3). Decompression to a small 3 ton load at
   T-a and holding for 24 hours did not induce any phase transformation,
   and the starting 0 GPa alpha-LiAlD4 structure was eventually recovered.
   Heating from T-a to 60 degrees C while under compression to 7.15 GPa
   produces new and intense reflections in the diffraction pattern, while
   also retaining alpha-LiAlD4 reflections, indicating a two-phase
   alpha/beta-LiAlD4 mixture. The beta-LiAlD4 structure indexed from this
   data is in the monoclinic space group I2/b, with unit cell dimensions
   a=4.099(3) angstrom, b=4.321(4) angstrom, c=10.006(7) angstrom,
   gamma=88.43(2)degrees, yielding a volumetric efficiency of 151.2 kg
   D-2/m(3). The atomic arrangement in I2/b is identical to that in the
   theoretically predicted I4(1)/a super group, with isolated symmetric
   AlD4 tetrahedra displaying Al - D distances of 1.545(2) angstrom. Once
   again, decompression and cooling recovers the ambient alpha-LiAlD4


Svoboda, J   Zima, V   Benes, L   Melanova, K   Vicek, M
Synthesis and characterization of new calcium phenylphosphonates and
INORGANIC CHEMISTRY 44, 2005, 9968-9978.
Three new calcium phenylphosphonates, CaC6H5PO3-2H(2)O,
   Ca-3(C6H5PO3H)(2)(C6H5PO3)(2)(.)4H(2)O, and CaC6H5PO3. H2O, and two
   calcium 4-carboxyphenylphosphonates, Ca(HOOCC6H4PO3H)2 and
   Ca-3(OOCC6H4PO3)(2)(.)6H(2)O, were prepared. It was found that
   CaC6H5PO3-2H2O transformed into previously known Ca(C6H5PO3H)(2) via
   Ca-3(C6H5PO3H)(2)(C(6)H5PO(3))(2)(.)4H(2)O in the presence of
   phenylphosphonic acid, and vice versa, Ca(C6H5PO3H)(2) turned into
   CaC(6)H(5)PO(3)(.)2H(2)O in a weak basic medium. A similar relationship
   was found between Ca(HOOCC6H4PO3H)(2) and Ca-3(OOCC6H4PO3)(2)(.)6H(2)O;
   i.e., Ca-3(OOCC6H4PO3)2(.)6H(2)O transformed into Ca(HOOCC6H4PO3H)(2)
   in the presence of 4-carboxyphenylphosphonic acid. On the contrary,
   Ca-3(OOCC6H4PO3)2(.)6H(2)O is formed from Ca(HOOCC6H4PO3H)(2) in the
   presence of ammonium as a weak base. The structure of
   Ca(HOOCC6H4PO3H)(2) was solved from X-ray powder diffraction data by an
   ab initio method using a FOX program. The compound is monoclinic, space
   group C21c (No, 15), a = 49,218(3) angstrom, b = 7.7609(4) angstrom, c
   = 5.4452(3) angstrom, beta = 128.119(3)degrees, and Z = 4. Its
   structure is one-dimensional with [Ca-2(HOOCC6H4PO3H)(4)](infinity)
   ribbons forming basic building blocks. The ribbons are held together by
   hydrogen bonds between carboxylic groups.

2005-75  ???

Barrier, N   Pelloquin, D   Nguyen, N   Giot, M   Bouree, F   Raveau, B
Ferrite Sr3NdFe3O9: An original intergrowth between the brownmillerite
   and K2NiF4-type structures
CHEMISTRY OF MATERIALS 17, 2005, 6619-6623.
The coupled neutron diffraction and Mossbauer study of the layered
   oxide Sr3NdFe3O9 shows for the first time the possibility of anionic
   vacancies ordering in an oxygen-deficient related
   Ruddlesden-Popper(RP-) type ferrite leading to an original intergrowth
   of brownmillerite and K2NiF4-type layers. The antiferromagnetic
   properties of this phase up to 500 K are also evidenced. These results
   open the route to the synthesis of new members in the series
   (Sr2Fe2O5)(n) .  SrLnFeO(4) and to the understanding of their
   reactivity with atmospheric water.


Karau, F
   Schnick, W
Preparation and crystal structure of diammin magnesium diazide
Diammin magnesium diazide was synthesized from Mg3N2 and NH4N3 in
   liquid ammonia and crystallized at 150 degrees C under autogenous
   atmosphere of HN3 and NH3 using sealed ampoules. Mg(NH3)(2)(N-3)(2) is
   a colorless, microcrystalline powder which can detonate above 180
   degrees C. Caution, preparation and manipulation of Mg(NH3)(2)(N-2)(2)
   is very dangerous! The crystal structure was solved from powder data
   using the Patterson method and a Rietveld refinement was performed
   (Mg(NH3)(2)(N-3)(2), I 4/m, no. 87; a = 6.3519(1), c = 7.9176(2)
   angstrom; Z = 2, R(F-2) = 0.1162). The crystal structure of
   Mg(NH3)(2)(N-3)(2) is related to that of SnF4. It consists of planes
   built up from corner sharing Mg(NH3)2(N3)4 octahedra connected
   equatorially over their four azide bridges with the ammonia ligands
   being in trans position. IR data were collected and interpreted in
   accordance with the structural data.
2005-77  ??

Marinkovic, BA   Jardim, PM   de Avillez, RR   Rizzo, F
Negative thermal expansion in Y2Mo3O12
SOLID STATE SCIENCES 7, 2005, 1377-1383
The crystal structure of Y2Mo3O12 was refined by the Rietveld method
   for 130 degrees C as orthorhombic with space group Pbcn (No. 60). It is
   isostructural to Fe2Mo3O12 and consists of vertex sharing YO6 and MoO4
   building polyhedra. Y2Mo3O12 has very high negative thermal expansion
   along all three crystallographic directions in the 130-900 degrees C
   temperature range. The overall linear coefficient of thermal expansion
   (alpha(1) = alpha(v)/3) is -1.26 x 10(-5) degrees C. Water molecules
   enter freely in Y2Mo3O12 microchannels and seem to have a role in
   partial amorphization of this compound at room temperature.

Littner, A   Francois, M   Tobola, J   Elkaim, E   Malaman, B   Vilasi, M
Molten glass corrosion resistance of new Mo-Ru-Si compounds
AB In spite of a very promising potential for a large field of high
   temperature applications, MoSi2 shows only a limited resistance against
   molten glass corrosion. Efforts to improve the performance of
   MoSi2-based materials led to the investigation of the Mo-Ru-Si phase
   diagram. The isothermal section at 1673 K revealed five new
   intermetallics with original structures. The crystallographic study of
   two of them was made using standard and synchrotron X-ray measurements
   combined with KKR (Korringa-Kohn-Rostoker) calculations. The use of
   such total energy electronic structure calculations was helpful in
   order to localize accurately Mo and Ru in the new compound
   beta-Mo26Ru47Si27. This compound crystallizes in P4/mmm space group
   with a = 9.2164(l) angstrom, c = 2.88721 (1) angstrom, Dx = 9.69(1)
   g/cm(3). The structure has been refined by the Rietveld method down to
   R-p = 1. 1 %, R-B = 12.0 %, R-F = 8.7% for 6814 ob-served data and 271
   independent reflections. Moreover, electrochemical techniques enabled
   the determination of the redox properties of the new intermetallic
   compounds. It has been shown that, in contact with molten glass at 1623
   K, Mo-Ru-Si compounds were subjected to electrochemical reactions
   leading to the simultaneous oxidation of silicon and molybdenum. The
   progressive superficial depletion of Si and Mo resulted in the more or
   less rapid formation of a thick, porous and low adherent Ru-layer.
   Consequently, the results showed that Ru-additions had no positive
   effect on the molten glass corrosion resistance of MoSi2-based
   materials. The formation of a porous Ru-layer should even accelerate
   the degradation kinetics through galvanic coupling occurring between
   the superficial layer and the bulk material.

2005-79   ???

Li, LY   Li, GB   Wang, YX   Liao, FH   Lin, JH
Bismuth borates: Two new polymorphs of BiB3O6
INORGANIC CHEMISTRY 44, 2005, 8243-8248.
Two new polymorphs of BiB3O6 were identified at low temperatures using
   boric acid as a flux. Unlike alpha-BiB3O6, which crystallizes in a
   noncentrosymmetric space group and, thus, shows exceptional nonlinear
   optical (NLO) properties, beta-BiB3O6 (I) and gamma-BiB3O6 (II)
   crystallize in the centrosymmetric space group P2(1)/n with the
   following lattice parameters: a = 14.1664(I), b = 6.7514(I), c =
   4.4290(I) angstrom, beta = 102.125(I)degrees for I; and a = 8.4992(I),
   b = 11.7093(I), c = 4.2596(I) angstrom, beta = 121.141(I)degrees for
   II. However, from the structural point of view, the three polymorphs of
   BiB3O6 are closely related. The structure of beta-BiB3O6 (I) contains a
   2-dimensional borate layer, which could be considered to be an
   intralayered additive product of alpha-BiB3O6. On the other hand, the
   3-dimensional borate framework in gamma-BiB3O6 (II) could be considered
   to be an interlayered additive product of beta-BiB3O6 (I). According to
   the synthesis experiments and calculated density, it is proposed that
   compounds I and II should be the low-temperature (high-pressure)
   polymorphs of BiB3O6.

2005-80  ???

Oliveira, MF   Kycia, SW   Gomez, A   Kosar, AJ   Bohle, DS
   Hempelmann, E   Menezes, D   Vannier-Santos, MA   Oliveira, PL   Ferreira, ST
Structural and morphological characterization of hemozoin produced by
   Schistosoma mansoni and Rhodhius prolixus
FEBS LETTERS 579, 2005, 6010-6016.
Hemozoin (Hz) is a heme crystal produced upon the digestion of
   hemoglobin (Hb) by blood-feeding organisms as a main mechanism of heme
   disposal. The structure of Hz consists of heme dimers bound by
   reciprocal iron-carboxylate interactions and stabilized by hydrogen
   bonds. We have recently described heme crystals in the blood fluke,
   Schistosoma mansoni, and in the kissing bug, Rhodnius prolixus. Here,
   we characterized the structures and morphologies of the heme crystals
   from those two organisms and compared them to synthetic P-hematin (beta
   H). Synchrotron radiation X-ray powder diffraction showed that all heme
   crystals share the same unit cell and structure. The heme crystals
   isolated from S. mansoni and R. prolixus consisted of very regular
   units assembled in multicrystalline spherical structures exhibiting
   remarkably distinct surface morphologies compared to beta H. In both
   organisms, Hz formation occurs inside lipid droplet-like particles or
   in close association to phospholipid membranes. These results show, for
   the first time, the structural and morphological characterization of
   natural Hz samples obtained from these two blood-feeding organisms.
   Moreover, Hz formation occurring in close association to a hydrophobic
   environment seems to be a common trend for these organisms and may be
   crucial to produce very regular shaped phases, allowing the formation
   of multicrystalline assemblies in the guts of S. mansoni and R.


Barros-Garcia, FJ   Bernalte-Garcia, A   Cumbrera, FL   Lozano-Vila, AM
   Luna-Giles, F   Melendez-Martinez, JJ   Ortiz, AL
Synthesis, molecular characterization by infrared spectroscopy, and
   crystal structure determination by X-ray powder diffractometry of
POLYHEDRON 24, 2005, 1975-1982.
The title zinc(II) complex, dichloro[2-(3,4-dichlorophenyl)imino-kappa
   N-N-(2-thiazin-kappa N-2-yl)thiazolidine]zinc(II), was synthesized in
   the form of small crystals unsuitable for structure determination by
   X-ray single-crystal diffractometry. It was therefore characterized
   firstly in the solid state by elemental analysis and infrared
   spectroscopy, and then its crystal structure was determined by X-ray
   powder diffractometry. The procedure followed to resolve the crystal
   structure used direct-space methods with a 'MonteCarlo/parallel
   tempering' search algorithm, where the starting configuration was
   obtained by means of infrared spectroscopy and molecular mechanics. A
   final refinement of the crystal structure was performed using the
   Rietveld method. It was found that the environment around the zinc(II)
   ion may e described as a distorted tetrahedral geometry, with the
   metallic atom coordinated to two chlorine atoms [Zn-Cl(1) = 2.158(5)
   angstrom; Zn-Cl(2) = 2.145(4) angstrom], one imino nitrogen [Zn-N(3) =
   2.237(4) angstrom] and one thiazine nitrogen [Zn-N(1) = 2.273(5)
   angstrom]. In addition, we also report in this study the crystal
   structure of the
   2-(3,4-dichlorophenyl)imino-N-(2-thiazin-2-yl)thiazolidine (TdTz)
   ligand determined by X-ray single-crystal diffractometry.


Miller, SR   Lear, E   Gonzalez, J   Slawin, AMZ
   Wright, PA   Guillou, N   Ferey, G
Synthesis and structure of the framework scandium methylphosphonates
   ScF(H2O)CH3PO3 and NaSc(CH3PO3)(2) .  0.5H(2)O
DALTON TRANSACTIONS 20, 2005, 3319-3325.
Two framework scandium methylphosphonates have been prepared
   hydrothermally and their structures solved. ScF(H2O) CH3PO3 is a
   non-porous solid built up from - ScF - chains linked by
   methylphosphonate groups. The ScO4F2 octahedra are completed by a
   coordinated water molecule. NaSc(CH3PO3)(2)  .  0.5H(2)O was
   solved ab initio from high-resolution synchrotron X-ray powder
   diffraction data. It has a fully connected, negatively charged scandium
   phosphonate framework where ScO6 octahedra share vertices with PO3CH3
   groups. The solid contains charge balancing sodium cations, coordinated
   by a water molecule, which may be reversibly removed and adsorbed. The
   structure of the perdeuterated, dehydrated solid has been refined
   against neutron powder diffraction data collected at 2.5 K, showing the
   CD3 groups in a fully staggered orientation with respect to the
   phosphonate oxygen atoms.


Belik, AA   Azuma, M   Matsuo, A   Whangbo, MH   Koo, HJ
   Kikuchi, J   Kaji, T   Okubo, S   Ohta, H   Kindo, K   Takano, M
Investigation of the crystal structure and the structural and magnetic
   properties of SrCu2(PO4)(2)
INORGANIC CHEMISTRY 44, 2005, 6632-6640.
SrCu2(PO4)(2) was prepared by the solid-state method at 1153 K. Its
   structure was solved by direct methods in the space group Pccn (No. 56)
   with Z = 8 from synchrotron X-ray powder diffraction data measured at
   room temperature. Structure parameters were then refined by the
   Rietveld method to obtain the lattice parameters, a = 7.94217(8)
   angstrom, b = 15.36918(14) angstrom, and c = 10.37036(10) angstrom.
   SrCu2(PO4)(2) presents a new structure type and is built up from Sr2O16
   and Cu1Cu(2)O(8) units with Cu1 (...) Cu2 = 3.256 angstrom. The
   magnetic properties of SrCu2(PO4)(2) were investigated by magnetic
   susceptibility, magnetization up to 65 T, Cu nuclear quadrupole
   resonance (NQR), electron-spin resonance, and specific heat
   measurements. With spin-dimer analysis, it was shown that the two
   strongest spin-exchange interactions between Cu sites result from the
   Cu1-0 (...) O-Cu2 and Cu2-0 (...) O-Cu2 super-superexchange paths with
   Cu1 (...) Cu2 = 5.861 angstrom and Cu2 (...) Cu2 = 5.251 angstrom, and
   the superexchange associated with the structural dimer Cu1Cu2O(8) is
   negligible. The magnetic susceptibility data were analyzed in terms of
   a linear four-spin cluster model, Cu1-Cu2-Cu2-Cu1 with -2J(1)/k(B) =
   82.4 K for Cu1-Cu2 and -2J(2)/k(B) = 59 K for Cu-Cu2. A spin gap
   deduced from this model (Delta/k(B) = 63 K) is in agreement with that
   obtained from the Cu NQR data (Delta/k(B) = 65 K), A one-half
   magnetization plateau was observed between approximately 50 and 63 T at
   1.3 K. Specific heat data show that SrCu2(PO4)(2) does not undergo a
   long-range magnetic ordering down to 0.45 K. SrCu2(PO4)(2) melts
   incongruently at 1189 K. We also report its vibrational properties
   studied with Raman spectroscopy.


Galli, S   Masciocchi, N   Cariati, E   Sironi, A
   Barea, E   Haj, MA   Navarro, JAR   Salas, JM
Quest for second-harmonic-generation-active coordination polymers:
   Synthesis and properties of silver(I) pyrimidinolates
CHEMISTRY OF MATERIALS 17, 2005, 4815-4824.
In the search for coordination compounds showing significant second
   harmonic generation (SHG) activity, reaction of Ag(I) ions with the
   4-hydroxypyrimidine (4-Hpymo) and 5-nitro-2-hydroxypyrimidine (HNP)
   ligands generated four crystalline ID polymers, Ag(4-pymo) .
   nH(2)O (n = 2.5, 0), Ag(NP)(NH3), and Ag(NP), the latter two
   crystallizing in acentric space groups. Their synthesis, complete
   characterization, and structural determination, by conventional
   single-crystal and laboratory X-ray powder diffraction methods, are
   presented and discussed in the frame of diazaaromatic-ligand- and
   metal-containing species. XRPD has also allowed the detection of the
   polyhydrated, elusive Ag(4-pymo) .  nH(2)O (n = 2, 3) species.
   Powders of Ag(NP) have shown an SHG activity close to that of standard
   urea. By applying the geometrical model proposed by Zyss, it is shown
   that the NP ligand is a highly promising chromophore, the oxo and nitro
   functionalities cooperatively promoting a high hyperpolarizability.

2005-85   ???
Staunton, E   Andreev, YG   Bruce, PG
Structure and conductivity of the crystalline polymer electrolyte
   beta-PEO6 : LiAsF6

2005-86   ???

Li, LY   Li, GB   Wang, YX   Liao, FH   Lin, JH
Bismuth borates: One-dimensional borate chains and nonlinear optical
CHEMISTRY OF MATERIALS 17, 2005, 4174-4180.
Three bismuth borates, Bi[B4O6(OH)(2)]OH (I), BiB2O4F (II), and
   Bi-3[B6O13(OH)] (III), were obtained in boric acid flux at low
   temperatures and their structures were determined by using
   single-crystal and powder X-ray diffraction techniques. All these three
   bismuth borates contain one-dimensional borate chains and crystallize
   in noncentrosymmetric space groups. I is a hydrated borate,
   crystallizing, in the space group PI with lattice constants a =
   4.300(1) angstrom, b = 8.587(2) angstrom, c = 10.518(2) angstrom, alpha
   = 113.11(3)', 100.50(3)degrees, and beta = 90.36(3)degrees, and the
   borate chain consists of a 3-ring (2BO(3) + BO4) and a BO3 group. II is
   a fluoroborate, which crystallizes in the trigonal space group P3(2)
   with a = 6.7147(1) angstrom and c = 6.4688(1) angstrom, and the borate
   anion is a 3-fold helix chain formed by extensive linkage of
   three-membered borate rings (3BO(4)). III is also a hydrated borate
   with a structure that is closely related to 11, in which one-sixth of
   the borate groups are in triangular geometry (BOA which reduces the
   symmetry to P1, a = 6.6257(1) angstrom, b =6.6238(1) angstrom, c =
   6.6541(1) angstrom, and alpha = 89.998(3)degrees, beta =
   89.982(2)degrees, and gamma = 119.992(2)degrees. All these three
   bismuth borates exhibit nonlinear optical (NLO) properties.


Dorset, DL   Kennedy, GJ
Crystal structure of MCM-70: A microporous material with high framework
JOURNAL OF PHYSICAL CHEMISTRY B 109, 2005, 13891-13898.
The crystal structure of the borosilicate MCM-70 (siliceous framework
   formula Si12O24) was determined from synchrotron powder diffraction
   data with the program FOCUS. The framework crystallizes in space group
   Pmn2(1), where a = 13.663, b = 4.779, c = 8.723 angstrom, and forms ID
   ellipsoidal 10-ring channels with the following dimensions: 5.0 x 3.1
   angstrom. Rietveld refinement of the model against synchrotron powder
   data from solvated material gives Rwp = 0.15, R(F-2) = 0.11. In
   addition to the four tetrahedral sites and seven framework oxygens, one
   potassium position is found during this refinement. Because of the
   unreasonable geometry of five putative extraframework oxygen sites,
   another synchrotron pattern was obtained from a dehydrated specimen. A
   refinement in space group P1n1 (removing the mirror operation of
   Pmn2(1)), where a = 13.670, b = 4.781, c = 8.687 angstrom, and beta =
   90.24 degrees, verified that the previous framework geometry is
   preserved as well as the potassium position. One extraframework oxygen
   was located that would yield a reasonable K-O distance. The existence
   of potassium is verified by electron energy dispersive spectroscopic
   measurements as well as quantitative elemental analysis. (There are
   approximately 2.35 K sites per 12 Si in the unit cell.) It is likely
   that the constricted channels occlude KOH. B-11 and Si-29 MAS NMR
   measurements indicate a framework SiO2/B2O3 of approximately 40:1,
   which is consistent with a wavelength dispersive spectroscopic
   measurement. The silicate framework density is 2.10 gm/cm(3). The
   resulting framework density for T sites, 21.1, is unusually high for a
   zeolite, just below the value for paracelsian (21.4) or scapolite
   (21.8), each of which also has a smallest four-ring loop. The H-1 ->
   Si-29 CP MAS measurements suggest sample heterogeneity, that is, a
   portion of the sample that is strongly coupled to hydrogen and
   efficiently cross polarizes and another portion that does not.


Li, LY   Liao, FH   Li, GB   Lin, JH
Synthesis and structure of a novel hydrated rare earth polyborate,
   Ln[B5O8(OH)(2)] (Ln=Pr, Nd)
A novel hydrated rare earth polyborate, Ln[B5O8(OH)(2)] (Ln=Pr, Nd) has
   been synthesized by using boric acid as a flux at 200 degrees C. Its
   crystal structure is established by powder X-ray diffraction technique.
   Ln[B5O8(OH)(2)] crystallizes in monoclinic space groupP2(1)/c. The
   title compounds consist of a double three-membered ring composed of
   three BO4 and two BO3 groups as the fundamental building block. The FBB
   shares four common oxygen atoms with the adjacent FBBs, producing a
   borate layer containing nine-membered borate ring window, of which the
   rare earth cations are located around the center. The Ln(3+) cations
   are coordinated with ten oxygen atoms from the nine-membered ring
   window and the adjacent borate layer. The borate layers are stacked
   along the b axis and are interlinked by the Ln-O bond.


Irran, E   Jurgens, B   Schmid, S   Schnick, W
Synthesis, crystal structure determination from X-ray powder
   diffractometry and vibrational spectroscopic properties of
   Mg[N(CN)(2)](2)  .  4H(2)O
Magnesium dicyanamide tetrahydrate Mg[N(CN)(2)](2)(.)4 H2O was
   synthesized by aqueous ion exchange starting from Na[N(CN)(2)] and
   Mg(NO3)(2)(.)6 H2O. The crystal structure was solved and refined on the
   basis of powder X-ray diffraction data (P-21/c, Z = 2, a 737.50(2), b =
   732.17(1), c = 971.67(2) pm, beta = 98.074(1)degrees, wR(P) = 0.059,
   R-P = 0.046, R-F = 0.075). In the crystal there are neutral complexes
   [Mg[N(CN)(2)](2)(H2O)(4)] Which arc only connected via hydrogen bonds.
   Above 40 degrees C the tetrahydrate decomposes into anhydrous


Barbier, J   Penin, N   Cranswick, LM
Melilite-type borates Bi2ZnB2O7 and CaBiGaB2O7
CHEMISTRY OF MATERIALS 17, 2005, 3130-3136.
The bismuth borates Bi2ZnB2O7 and CaBiGaB2O7 have been synthesized by
   solid-state reactions at temperatures in the 650-825 degrees C range at
   1 atm pressure. These compounds are the only synthetic diborate members
   of the melilite family, A(2)XZ(2)O(7), in which layers of A cations
   alternate with XZ(2)O(7) tetrahedral layers. Except for CdBiGaB2O7, the
   synthesis of other substituted bismuth borate melilites has been
   unsuccessful. The crystal structures of Bi2ZnB2O7 and CaBiGaB2O7 have
   been determined by powder X-ray diffraction and refined by the Rietveld
   method using powder neutron diffraction data. CaBiGaB2O7 adopts the
   regular tetragonal melilite structure (P $(4) over bar $2(1)m space
   group, Z = 2) containing B2O7 tetrahedral dimers. The refinement of
   split eight-coordinated sites for the Ca2+ and Bi3+ interlayer cations
   suggests the presence of additional disorder. Bi2ZnB2O7 adopts a unique
   orthorhombic melilite superstructure (Pba2 space group, Z = 4)
   containing both tetrahedral B2O7 and triangular B2O5 dimers. The Bill
   cations occupy two distinct interlayer sites with strongly asymmetric
   6-fold coordination environments. The preliminary measurement of second
   harmonic generation efficiencies (d(eff)) of powder samples has yielded
   values of 4.0 (Bi2ZnB2O7) and 1.6 (CaBiGaB2O7) relative to a KH2PO4


Ikeda, T    Itabashi, K
RMA-3: synthesis and structure of a novel Rb-aluminosilicate zeolite
CHEMICAL COMMUNICATIONS iss 21, 2005, 2753-2755.
RMA-3 (Rubidium Microporous Aluminosilicate-3) was hydrothermally
   synthesized from rubidium-aluminosilicate gels without using any
   organic or inorganic additives, and its structure determined by XRD
   Rietveld analysis was confirmed as a novel framework topology
   containing two 8-membered ring pore-openings with dimensions of 0.49 x
   0.37 nm and 0.34 x 0.38 nm.


Chi, LS   Swainson, I   Cranswick, L   Her, JH   Stephens, P   Knop, O
The ordered phase of methylammonium lead chloride CH3ND3PbCl3
The perovskite-structured compound methylammonium lead chloride orders
   into a low-temperature phase of space group Pnma, in which at 80 K each
   of the orthorhombic axes a = 11.1747(2) &ANGS;, b = 11.3552(1) &ANGS;,
   and c = 11.2820(1) &ANGS; is doubled with respect to the room
   temperature disordered cubic phase (a = 5.669 &ANGS;). The structure
   was solved by ab initio methods using the programs EXPO and FOX. This
   unusual cell basis for space group Pnma is not that of a standard tilt
   system. This phase, in which the methylammonium ions, are ordered shows
   distorted octahedra. The octahedra possess a bond angle variance of
   60.663(&DEG; 2) and a quadratic elongation of 1.018, and are more
   distorted than those in the ordered phase of methylammonium lead
   bromide. There is also an alternating long and short Pb-Cl bond along
   a, due to an off-center displacement of Pb within the octahedron. This
   suggests that the most rigid unit is actually the methylammonium
   cation, rather than the PbCl6 octahedra, in agreement with existing
   spectroscopic data.


Drache, M   Roussel, P   Conflant, P   Wignacourt, JP
Bi17Yb7O36 and BiYbO3 crystal structures. Characterization of thulium
   and lutetium homologous compounds
SOLID STATE SCIENCES 7, 2005, 269-276.
Two new compounds Bi17Yb7O36 and BiYbO3 which were recently evidenced
   in the Bi2O3-Yb2O3 system, have been characterized and their structure
   determined from X-ray diffraction powder data using the Rietveld method
   in an orthorhombic and a triclinic lattice, respectively. The thulium
   and lutetium homologous compounds have been prepared for the first
   time. They are isostructural to the ytterbium homologous. The six
   compounds have been characterized versus temperature by DTA, X-ray
   thermodiffractometry, and they systematically show a transformation
   from their low temperature form, to a delta-Bi2O3-type phase, occurring
   on heating. For Bi(17)Ln(7)O(36), the delta-type phase is obtained,
   directly with Ln = Lu (870 degrees C) and Yb (855 degrees C), and only
   after an intermediate biphasic orthorhombic-cubic mixture in the range
   780-825 degrees C for Ln = Tm. For BiLnO(3), there is a large
   two-phased domain (delta-Bi2O3 + Ln(2)O(3) related phases) from 955 to
   1100 degrees C for Lu, 970 to 1200 degrees C for Yb and 980 to 1270
   degrees C for Tm. The lattice constants thermal expansion coefficients
   have been determined from the cell parameters evolutions versus
   temperature. The conductivity properties of the Bi(17)Ln(7)O(36)
   series, which could be obtained as ceramic pellets after sintering in
   the stability range of their low-temperature forms, have been


Majzlan, J   Botez, C   Stephens, PW
The crystal structures of synthetics Fe-2(SO4)(3)(H2O)(5) and the type
   specimen of lausenite
AMERICAN MINERALOGIST 90, 2005, 411-416.
An iron sulfate of nominal composition Fe-2(SO4)(3)(H2O)(5) has been
   synthesized and its structure determined and refined by high resolution
   powder diffraction using synchrotron radiation. The structure consists
   of corrugated slabs in which iron octahedra are linked by sulfate
   tetrahedra in the monoclinic space group P2(1)/m with lattice
   parameters a = 10.711(1), b = 11.085(1), and c = 5.5747(5) Angstrom,
   beta = 98.853(3)degrees. We compare these results with the type
   specimen of lausenite from Jerome, Arizona, which has monoclinic
   lattice parameters a = 10.679(2), b = 11.053(3), and c = 5.567(1)
   Angstrom, beta = 98.89(1)degrees. Weight loss experiments show that it
   is currently a pentahydrate, despite earlier reports that lausenite is
   a hexahydrate. We argue that our synthetic material provides a
   structure determination for the type specimen of lausenite.


Jurgens, B   Irran, E   Schnick, W
Synthesis and characterization of the rare-earth dicyanamides
   Ln[N(CN)(2)](3) with Ln = La, Ce, Pr, Nd, Sm, and Eu
The rare-earth dicyanamides Ln[N(CN)(2)](3) (Ln = La, Ce, Pr, Nd, Sm,
   Eu) were obtained via ion exchange in aqueous medium and subsequent
   drying: The crystal structures were solved and refined based on X-ray
   powder diffraction data and they were found to be isotypic:
   Ln[N(CN)(2)](3); Cmem (no. 63), Z = 4, Ln = La: a = 799.88(9) pm, b =
   11 58.2(1) pin, c = 1026.7(1) pm; Cc: a = 794.94(3) pm, b =
   1152.15(4)pm, c = 1020.96(4)pm; Pr: a = 790.45(5)pm, b = 1146.19(6)pm,
   c = 1016.74(6)pm; Nd: a 787.79(3)pm, b = 1144.59(4)pm, c =
   1015.54(4)pm; Sm: a = 781.30(5)pm, b = 1138.64(6)pm, c = 1012.04(5)pm;
   Eu: a 776.7(1)pm, b = 113 5. 1 (1) pm, c = 10 1 3.7(1) pm). The
   compounds represent the first dicyanamides with trivalent cations. The
   Ln(3+) ions are coordinated by three bridging N atoms and six terminal
   N atoms of the dicyanamide ions forming a three capped trigonal prism.
   The structure type is related to that of PuBr3. The novel compounds
   Ln[N(CN)(2)](3) have been characterized by IR and Raman spectroscopy
   (Ln = La) and the thermal behavior has been monitored by differential
   scanning calorimetry (Ln = Ce, Nd, Eu).

2005-96  ??

Li, ZF   Sun, JL   Wang, YX   You, LP   Lin, JH
Structural and magnetic properties of Ba3La3Mn2W3O18
A quaternary phase, Ba3La3Mn2W3O18, was synthesized in reduced
   atmosphere (5% H-2/Ar) at 1200degreesC and characterized by using
   powder X-ray diffraction, electron diffraction and high resolution TEM.
   Ba(3)La(3)Mn(2)W3O(18) crystallizes in rhombohedral space group R $(3)
   over bar $m with the cell parameters, a = 5.7371(1) Angstrom and c =
   41.8336(5) Angstrom, and can be attributed to the n = 6 member in the
   B-site deficient perovskite family, A(n)B(n)-O-1(3n). The structure can
   be described as close-packed [La/BaO3] arrays in the sequence of
   (hcccch)(3), wherein the B-site cations, W and Mn, occupy five
   octahedral layers in every six octahedral layers, which leave a vacant
   octahedral layers separating the 5-layer perovskite blocks. The
   B-cation layers in the perovskite block alternate along the c-axis in a
   sequence of W6+-Mn2+ -W5+ -Mn2+- W6+. The bond valence calculation and
   optical reflection spectrum confirm the presence of W5+. This compound
   behaves paramagnetically in wide temperature range and weak
   antiferromagnetic interaction only occurs at low temperatures.


Tyutyunnik, AP   Zubkov, VG   Krasil'nikov, VN   Svensson, G   Sayagues, MJ
Crystal structure of K2V8O21 and Tl2V8O21
SOLID STATE SCIENCES 7, 2005, 37-43.
The crystal structures of K2V8O21 and Tl2V8O21 have been determined and
   refined, using both neutron and X-ray powder diffraction data. K2V8O21
   (TI2V8O21) crystallises in the monoclinic space group C2/m (C2/m) with
   the unit cell parameters a = 14.9402(2) (15.1405(4)) Angstrom, b =
   3.61823(4) (3.61309(6)) Angstrom, c = 14.7827(2) (14.9712(2)) Angstrom
   and beta = 91.072(1)degrees (89.967(2)degrees). The structures consist
   of VO6 octahedra and VO5 pyramids forming [V8O21](2-) units running
   along the b axis. These units can then be divided into three columns:
   (i) two edge-sbaring VO5 pyramids, (ii) columns of rock-salt type
   structure and (iii) single chains of VO5 pyramids. The KM ions are
   found in tunnels formed by the [V8O2](2-) units.


Barrier, N   Michel, C   Maignan, A   Hervieu, M   Raveau, B
CaMn4O8, a mixed valence manganite with an original tunnel structure
A new mixed valent manganite CaMn4O8 with an original tunnel structure
   has been synthesized. The host lattice of this oxide has been
   determined by X-ray powder diffraction, using ab initio methods, and by
   high resolution electron microscopy. It consists of single and triple
   chains of edge-sharing MnO6 octahedra, interconnected through their
   apices. The [Mn4O8](infinity) framework delimits three types of
   tunnels: six-sided ("H") and eight-sided ("8") where sit the Ca2+
   cations, and empty rutile-like tunnels ("R"). The analysis of the Mn-O
   inter-atomic distances shows that this structure could also be
   described from the association of only single chains of edge-sharing
   MnO6 octahedra, with single chains of edge-sharing MnO5 pyramids, and
   evidences a high tendency of manganese to charge ordering.
   Nanostructural mechanisms investigated by electron microscopy also
   allow the structure to be described in terms of single bricks of four
   Mn polyhedra, and evidence twinning and intergrowth phenomena as well
   as local ordering of calcium in the tunnels. The magnetic measurements
   show strong antiferromagnetic fluctuations at low temperature, whereas
   the low value of T-N similar to 90 K indicates that the
   antiferromagnetic superexchange is weak in this oxide.


Schmidt, MU   Ermrich, M   Dinnebier, RE
Determination of the structure of the violet pigment C22H12Cl2N6O4 from
   a non-indexed X-ray powder diagram
The violet pigment methylbenzimidazolonodioxazine, C22H12Cl2N6O4
   (systematic name: 6,14-dichloro- 3,11-dimethyl-
   1,3,9,11-tetrahydro-5,13-dioxa-7,15-diazadiimidazo[ 4,5-b: 4',5'-m]
   pentacene-2,10-dione), shows an X-ray powder diagram consisting of only
   ca 12 broad peaks. Indexing was not possible. The structure was solved
   by global lattice energy minimizations. The program CRYSCA [ Schmidt &
   Kalkhof ( 1999), CRYSCA. Clariant GmbH, Pigments Research, Frankfurt am
   Main, Germany] was used to predict the possible crystal structures in
   different space groups. By comparing simulated and experimental powder
   diagrams, the correct structure was identified among the predicted
   structures. Owing to the low quality of the experimental powder diagram
   the Rietveld refinements gave no distinctive results and it was
   difficult to prove the correctness of the crystal structure. Finally,
   the structure was confirmed to be correct by refining the crystal
   structure of an isostructural mixed crystal having a better X-ray
   powder diagram. The compound crystallizes in P (1) over bar, Z = 1. The
   crystal structure consists of a very dense packing of molecules, which
   are connected by hydrogen bridges of the type N - H ... O=C. This
   packing explains the observed insolubility. The work shows that crystal
   structures of molecular compounds may be solved by lattice energy
   minimization from diffraction data of limited quality, even when
   indexing is not possible.


Brazdova, V   Ganduglia-Pirovano, MV   Sauer, J
Crystal structure and vibrational spectra of AlVO4. A DFT study
We present periodic density functional calculations within the
   generalized gradient approximation (Perdew-Wang 91) on structure and
   vibrational properties of bulk AlVO4. The optimized structure agrees
   well with crystallographic data obtained by Rietveld refinement (the
   mean absolute deviation of bond distances is 0.032 A), but the
   deviations are larger for the lighter oxygen atoms than for the heavier
   Al and V atoms. All observed bands in the Raman and IR spectrum have
   been assigned to calculated harmonic frequencies. Bands in the 1020-900
   cm(-1) region have been assigned to V-O-(2) stretches in V-O-(2)-Al
   bonds. The individual bands do not arise from vibrations of only one
   bond, not even from vibrations of several bonds of one VO4 tetrahedron.
   The results confirm that vibrations around 940 cm(-1) observed for
   vanadia particles supported on thin alumina film are V-O-Al interface
   modes with 2-fold coordinated oxygen atoms in the V-O-(2)-Al interface


Sperandeo, NR   Karlsson, A   Cuffini, S   Pagola, S   Stephens, PW
The crystal structure and physicochemical characteristics of
   2-hydroxy-N-[3(5)-pyrazolyl]-1,4-naphthoquinone-4-imine, a new
   antitrypanosomal compound
AAPS PHARMSCITECH 6, iss 4, 2005.
This study was designed to investigate the physical characteristics and
   crystalline structure of
   2-hydroxy-N-[3(5)pyrazolyl]-1,4-naphthoquinone-4-imine (PNQ), a new
   active compound against Trypanosoma cruzi, the causative agent of
   American trypanosomiasis. Methods used included differential scanning
   calorimetry, thermogravimetry, hot stage microscopy, polarized light
   microscopy (PLM), Fourier-transform infrared (FTIR) spectroscopy, and
   high-resolution X-ray powder diffraction (HR-XRPD). According to PLM
   and HR-XRPD data, PNQ crystallized as red oolitic crystals (absolute
   methanol) or prisms (dimethyl sulfoxide [DMSO]-water) with the same
   internal structure. The findings obtained with HR-XRPD data (applying
   molecular location methods) showed a monoclinic unit cell [a =
   18.4437(1) angstrom, b = 3.9968(2) angstrom, c = 14.5304(1) angstrom,
   alpha = 90, beta = 102.71(6)degrees, = 90 degrees, V = 1044.9(1)
   angstrom(3), Z = 4, space group P2(1)/c], and a crystal structure
   (excluding H-positions) described by parallel layers in the direction
   of the b-axis, with molecules held by homochemical (phenyl-phenyl and
   pyrazole-pyrazole) van der Waals interactions. In addition, FTIR
   spectra displayed the NH-pyrazole stretch overlapped with the OH
   absorption at 3222 cm(-1), typical of -NH and -OH groups associated
   through H-bondings; and a carbonyl stretching absorption at 1694
   cm(-1), indicating a non-extensively H-bonded quinonic C=O, which was
   in accordance with the solved crystal structure of PNQ. The existence
   of such cohesive forces shed light on the thermoanalytical data, which
   revealed that PNQ is a stable solid, unaffected by oxygen that
   decomposed without melting above 260 degrees C.


Sofina, N   Dinnebier, R   Jansen, M
The crystal structure of disodium phosphonate, Na2HPO3
Anhydrous disodium phosphonate, Na2HPO3, was prepared by dehydration of
   its pentahydrate. The crystal structure of Na2HPO3 was solved from high
   resolution X-ray powder diffraction data (P2(1)/n; Z = 4; a 9.6987(1),
   b = 6.9795(1), c = 5.0561 (1) angstrom, beta = 92.37(1)degrees; V =
   341.97(1) angstrom(3)). The crystal structure consists of two types of
   sodium-oxygen polyhedra, which are connected via common edges and
   vertices forming layers perpendicular to [100]. These Na(1)- and
   Na(2)-layers are interlinked via common edges, forming in a
   3D-framework. The resulting topology is providing oxygen arrangements
   that please the coordinative requirement of phosphorus(III).


Helliwell, JR   Helliwell, M   Jones, RH
Ab initio structure determination using dispersive differences from
   multiple-wavelength synchrotron-radiation powder diffraction data
The purpose of this paper and a test case study is to assess a method
   of ab initio structure solution from powder diffraction data using f'
   difference techniques. A theoretical foundation for the approach used
   is first provided. Then, with a test case ( nickel sulfate
   hexahydrate), it is shown that both the position of the anomalous
   scatterer (Ni) can be determined and the structure can be developed in
   full. Specifically, synchrotron-radiation data were collected at two
   wavelengths close to the K edge for Ni and three wavelengths remote
   from the Ni absorption edge, at 1.3, 1.8 and 2.16 angstrom. These five
   wavelengths then allowed various combinations to be tried to establish
   which wavelength pairs gave the optimum signal in the Patterson maps
   using dispersive amplitude differences. The initial phases derived from
   the metal-atom position then allowed the structure to be fully
   developed by difference Fourier cycling. The relevance of these
   developments to structure-solution possibilities for proteins via
   powder dispersive difference data is then outlined.


Dinnebier, RE   Nuss, H   Jansen, M
The crystal structures of solvent-free alkali-metal squarates from
   powder diffraction data
The crystal structures of solvent-free lithium, sodium, rubidium, and
   cesium squarates have been determined from high resolution synchrotron
   and X-ray laboratory powder patterns. Crystallographic data at room
   temperature of Li2C4O4: a = 7.1073(3) angstrom, b = 9.5627(4) angstrom,
   c = 3.2973(1) angstrom, beta = 101.11(1)degrees, V = 219.91 (1)
   angstrom(3), monoclinic, C2/m, Z = 2, Na2C4O4: a 3.4925(1) angstrom(3),
   b = 6.8152(1) angstrom, c = 10.3525(2) angstrom, beta = 91.56(1)degrees
   V = 246.32(1) angstrom(3), monoclinic, P2(1)/c, Z = 2; Rb2C4O4: a =
   10.7908(5) angstrom, b = 6.8494(3) angstrom, c = 4.4521(2) angstrom,
   beta = 92.39(0), V = 328.77(4) angstrom(3), monoclinic, C2/m, Z = 2;
   Cs2C4O4: a = 1.1768(3)angstrom, b = 7.0453(2)angstrom, c = 4.7424(1)
   angstrom, beta = 92.89(1)degrees; V = 372.97(4) angstrom(3),
   monoclinic, C2/m, Z = 2. The packing features of lithium squarate can
   be deduced from the AlB2 structure type, while sodium, rubidium, and
   cesium squarate are related to the CdI2 type. The relation between the
   two types of crystal structures of the squarate dianion is discussed.


Dinnebier, RE   Nuss, H   Jansen, M
Disodium rhodizonate: a powder diffraction study
The crystal structure of the title compound, disodium
   1,2,3,4-tetraoxo-5-cyclohexene-5,6-diolate, 2Na(+)  .  C6O62+,
   is built up of alternating layers of hexagonally packed Na+ cations and
   rhodizonate dianions. The rhodizonate dianion has a slightly twisted


Kirik, SD   Mulagaleev, RF   Blokhin, AI
[Pd-8(CH3COO)(8)(NO)(8)]: solution from X-ray powder diffraction data
The water-insoluble title compound, octakis(mu-acetato-kappa(2)O:O)
   octakis(mu-nitroso-kappa(2)N:O) octapalladium(II),
   [Pd-8(CH3COO)(8)(NO)(8)], was precipitated as a yellow powder from a
   solution of palladium nitrate in nitric acid by adding acetic acid. Ab
   initio crystal structure determination was carried out using X-ray
   powder diffraction techniques. Patterson and Fourier syntheses were
   used for atom locations, and the Rietveld technique was used for the
   final structure refinement. The crystal structure is of a molecular
   type. The skeleton of the [Pd-8(CH3COO)(8)(NO)(8)] molecule is
   constructed as a tetragonal prism with Pd atoms at the vertices. The
   eight NO- groups are in bridging positions along the horizontal edges
   of the prism. The N and O atoms of each nitroso group coordinate two
   different Pd atoms. The vertical edges present Pd  .   .
    .  Pd contacts with a short distance of 2.865 (1) angstrom.
   These Pd atoms are bridged by a pair of acetate groups in a cis
   orientation with respect to each other. The complex has
   crystallographically imposed 4/m symmetry; all C atoms of the acetate
   groups are on mirror planes. The unique Pd atom lies in a general
   position and has square-planar coordination, consisting of three O and
   one N atom.

Dinnebier, RE   Nuss, H   Jansen, M
Anhydrous CuC4O4, a channel structure solved from X-ray powder
   diffraction data
The crystal structure of the new anhydrous metal squarate CUC4O4 was
   solved from laboratory X-ray powder diffraction data. It crystallizes
   in the monoclinic space group I2/a (no. 15) with the lattice parameters
   a = 5.6747(1), b = 8.9394(4), c = 9.4987(4) angstrom und beta =
   94.372(2)degrees at ambient conditions (Z = 4, R-F(2) = 8.24%). The
   crystal structure can be reduced to a defect variant of the AIB(2) type
   of structure ([C4O4][Cu square] double left right arrow [Al][B-2]) and
   shows channels parallel to the a axis with a free diameter of about 2.3
   angstrom. The squarate dianion, [C4O4](2-), is acting as a
   mu(6)-ligand, in this case.


Solovyov, LA   Astachov, AM   Molokeev, MS   Vasiliev, AD
Powder diffraction crystal structure analysis using derivative
   difference minimization: example of the potassium salt of
The crystal structure of the potassium salt of 1-( tetrazol- 5- yl)-2-
   nitroguanidine [K(C2H3N8O2)] was solved and refined from X-ray powder
   diffraction data by applying the derivative difference minimization
   (DDM) method. The compound is of interest as an energetic substance.
   The structure model was found from a Patterson search. The reflection
   intensities for the Patterson synthesis were derived from the powder
   profile by applying a newly developed DDM-based profile decomposition
   procedure. The use of the DDM method allowed successful location and
   unconstrained refinement of all the atomic positions, including those
   of three independent H atoms. The advantages of DDM in terms of the
   precision and reproducibility of the structural parameters are
   discussed in comparison to Rietveld refinement results. The failure to
   refine the H-atom positions by the Rietveld method was attributed to
   systematic errors associated with the background modelling, which are
   avoided by DDM.


El-Himri, A   Nunez, P   Sapina, F   Beltran, A
Freeze-dried precursor-based synthesis of new polymetallic oxynitrides,
   V1-u-zCruMoz(OxNy),V1-u-zCruWz(OxNy), Cr1-u-zMouWz(OxNy) (u, z=0.2,
   0.33, 0.4, 0.6, u plus z < 1), and VzCrzMozWz(OxNy) (z=0.25)
Interstitial polymetallic oxynitrides in the solid solution series
   V1-u-zCruMoz(OxNy), V1-u-zCruWz(OxNy) and Cr1-u-zMouWz(OxNy) (u, z=0.2,
   0.33, 0.4, 0.6, u+z < 1), as well as the tetrametallic VzCrzMozWz(OxNy)
   (z=0.25) composition, can be obtained by ammonolysis of precursors
   resulting from the freeze-drying of aqueous solutions of the simple
   metal salts NH4VO3, (NH4)(2)CrO4, (NH4)(6)Mo(7)O(24) .  4H(2)O
   and (NH4)(6)W(12)O(39) .  18H(2)O. A study of the influence of
   the preparative variables on the outcomes of this procedure is
   presented. Compounds in the V1-u-zCruMoz(OxNy) series have been
   prepared as single phases by direct ammonolysis of the respective
   freeze-dried precursors during 2h at 1173 K, followed by fast cooling
   of the samples. In contrast, the preparation of compounds in both the
   V1-u-zCruWz(OxNy) and the Cr1-u-zMouWz(OxNy) series requires the
   intermediate formation of crystalline precursors. These last compounds
   result from thermal treatment in air at 973 K, during 12 h, of the
   corresponding freeze-dried powders. Then, they were subjected to
   ammonolysis, during 2 h, at 1123 K (V containing series) or 1173 K (Mo
   containing series), followed by slow cooling of the samples. The
   tetrametallic VzCrzMozWz(OxNy) compound also has been prepared as
   single phase by ammonolysis of the crystalline intermediate at 1073 K,
   during 2 h, followed by slow cooling. All the compounds in these series
   have the rock-salt crystal structure, in which the metal atoms are in a
   face-centred cubic arrangement, with non-metal atoms occupying
   octahedral interstitial positions. The materials have been
   characterized by X-ray powder diffraction, elemental analysis,
   thermogravimetric analysis under oxygen flow and scanning electron

Hildebrandt, L   Dinnebier, R   Jansen, M
Crystal structure and ionic conductivity of cesium trifluoromethyl
   sulfonate, CSSO3CF3
The crystal structures of the room and the high temperature
   modifications of cesium trifluoromethyl sulfonate were solved from high
   resolution X-ray powder diffraction data. At room temperature,
   alpha-CsSO3CF3 crystallizes in the monoclinic space group P2(1) with
   lattice parameters a = 9.7406(2) angstrom, b = 6.1640(1) angstrom, c =
   5.4798(1) angstrom, and beta = 104.998(1)degrees; Z = 2. At
   temperatures above T = 380 K, a second order phase transformation
   towards a disordered C-centered orthorhombic phase in space group Cmcm
   occurs with lattice parameters at T = 492 K of a = 5.5074(3) angstrom,
   b = 19.4346(14) angstrom, and c = 6.2978(4) angstrom; Z = 4. Within the
   crystal structures, the triflate anions are arranged in double layers
   with the apolar CF3-groups pointing towards each other. The cesium ions
   are located between the SO3-groups. CsSO3CF3 shows a specific ion
   conductivity ranging from sigma = 1.06  .  10(-8) Scm(-1) at T =
   393 K to sigma = 5.18  .  10(-4) Scm(-1) at T = 519 K.


Khalyavin, DD   Senos, AMR   Mantas, PQ
Crystal structure of La4Mg3W3O18 layered oxide
The crystal structure of A-site deficient La4M93W3O18 perovskite has
   been solved by x-ray powder diffraction in combination with group
   theoretical analysis. Above 700 K, the crystal structure is
   orthorhombic (space group Ibam; 2a(p) x 4a(p) x 2a(p) type
   superstructure) and presents a sequence of
   "-[Mg1/2W1/2O2] layers stacked along the b axis. The lanthanum ions and
   the vacancies in the [La1/3O]' and [La1/3O]" layers are ordered and
   form rows along the c axis. A half-period shift along the a direction
   between these layers leads to a quadrupling of the primitive perovskite
   unit cell in the b direction. The ordering of the vacancies in the
   lanthanum poor layers is connected with the ionic ordering between Mg2+
   and W6+ in the neighbouring [Mg1/2W1/2O2] blocks. Around 700 K, due to
   an anti-phase rotation of the octahedra, a continuous phase transition
   mediated by the Gamma(2)(+) irreducible representation from
   orthorhombic (Ibam, a(0)b(0)c(0)) to monoclinic (C2/m, a(0)b(0)c(-))
   symmetry takes place.


Li, DY   O'Connor, B   van Riessen, A   Mackinnon, C   Low, IM
Structural determination of high T-c superconductor (Bi,
   Pb)(2)Sr2Ca2Cu3Ox(2223) phase with powder diffraction data
The (Bi, Pb)(2)SrCa2Cu3Ox (2223) phase is regarded as the one of the
   most technologically significant high T-C phases in the Bi-Sr-Ca-Cu-O
   system. However, its structure has not been fully described so far. The
   definitive structure model of 2223 has been determined in this study by
   direct methods and Q-peak analysis of difference Fourier maps using
   synchrotron radiation data. Successive least squares refinement of the
   model with the preferred A2aa space group was carried out by Rietveld
   procedures with neutron diffraction data. Anomalies were not observed
   for interatomic distances (bonded and non-bonded atoms), bond angles
   and isotropic temperature parameters. Two categories of copper atoms
   were clearly identified: (i) square coordinated to four oxygen atoms
   and (ii) pyramids with a fifth oxygen atom. The valence states of two
   Cu atoms have been estimated using bond valence calculations, as
   employed by Brown for YBCO. There is no direct bridging between the Cu
   squares and pyramids. The Bi3+ cations are coordinated by three oxygen
   atoms and form a single chain [BiO2](n)(n-) along the a axis, which is
   the first report of this feature for the 2223 structure.


Vensky, S   Kienle, L   Dinnebier, RE   Masadeh, AS   Billinge, SJL   Jansen, M
The real structure of Na3BiO4 by electron microscopy, HR-XRD and PDF
The real structure of a new crystalline high temperature phase,
   metastable at room temperature, in the system sodium - bismuth -
   oxygen, beta-Na3BiO4, was determinated using high resolution X-ray
   powder diffraction, pair distribution function analysis, and high
   resolution transmission electron microscopy. beta-Na3BiO4 was
   synthesized by anodic oxidation of bismuth(III)-oxide in a sodium
   hydroxide - lithium hydroxide melt. The average crystal structure of
   beta-Na3BiO4 at ambient conditions (R(3) over bar m, a = 3.32141(9)
   angstrom, c = 16.4852(5) angstrom) is structurally related to
   alpha-NaFeO2 With metal layers almost statistically occupied in a Na:
   Bi ratio of 3: 1. Analysis of the long-range order on the bulk material
   by Rietveld refinement led to approximately Na: Bi ratios of 2: 1 and
   4: 1, in consecutive metal layers, while a detailed analysis of the
   local order by means of the pair distribution function revealed the
   existence of almost pure sodium layers and mixed 1: 1 - sodium: bismuth
   layers. Complementary studies on single crystallites using high
   resolution transmission electron miscroscopy exhibited a complex domain
   structure with short-range ordered, partially ordered, and long-range
   ordered domains.


Solovyov, LA   Belousov, OV   Dinnebier, RE   Shmakov, AN   Kirik, SD
X-ray diffraction structure analysis of MCM-48 mesoporous silica
The structure of MCM-48 mesoporous silicate materials has been fully
   characterized from X-ray diffraction data by applying recently
   developed methods of mesostructure analysis and full-profile
   refinement. The pore wall thickness of both as-made and calcined MCM-48
   was determined with high precision to be 8.0(1) Angstrom. No regular
   variations of the wall thickness were detected, but its density was
   found to be ca. 10% higher in the low-curvature regions. The surfactant
   density in the pores was assessed around 0.6-0.7 g/cm(3) and was found
   to have a distinct minimum in the pore center similar to that detected
   previously in MCM-41. A new extended model function of the density
   distribution in MCM-48 is proposed on the basis of the structural
   features that were revealed.


Dinnebier, RE   Vensky, S   Jansen, M   Hanson, JC
Crystal structures and topological aspects of the high-temperature
   phases and decomposition products of the alkali-metal oxalates
   M-2[C2O4] (M = K, Rb, Cs)
The high-temperature phases of the alkali-metal oxalates M-2[C2O4]
   (M=K, Rb, Cs), and their decomposition products M-2[CO3] (M=K, Rb, Cs),
   were investigated by fast, angle-dispersive X-ray powder diffraction
   with an image-plate detector, and also by simultaneous differential
   thermal analysis (DTA)/thermogravimetric analysis (TGA)/mass
   spectrometry (MS) and differential scanning calorimetry (DSC)
   techniques. The following phases, in order of decreasing temperature,
   were observed and crystallographically characterized (an asterisk
   denotes a previously unknown modification): *alpha-K-2[C2O4],
   *alpha-Rb-2[C2O4], *alpha-Cs-2[C2O4], alpha-K-2[CO3], *alpha-Rb-2[CO3],
   and *alpha-Cs-2[CO3] in space group P6(3)/mmc; *beta-Rb-2[C2O4],
   *beta-Cs-2[C2O4], *beta-Rb-2[CO3], and *beta-Cs-2[CO3] in Pnma;
   gamma-Rb-2[C2O4], gamma-Cs[C2O4], gamma-Rb-2[CO3], and gamma-Cs-2[CO3]
   in P2(1)/c; and delta-K-2[C2O4] and delta-Rb-2[C2O4] in Pbam. With
   respect to the centers of gravity of the oxalate and carbonate anions,
   respectively, the crystal structures of all known alkali-metal oxalates
   and carbonates belong to the AlB2 family, and adopt either the AlB2 or
   the Ni2In arrangement depending on the size of the cation and the
   temperature. Despite the different sizes and constitutions of the
   carbonate and oxalate anions, the high-temperature phases of the
   alkali-metal carbonates M-2[CO3] (M=K, Rb, Cs), exhibit the same
   sequence of basic structures as the corresponding alkali-metal
   oxalates. The topological aspects and order-disorder phenomena at
   elevated temperature are discussed.


Ahlert, S   Dinnebier, R   Jansen, M
The crystal structures of the high-temperature phases of Ag4Mn3O8
Two endothermic, reversible structural phase transitions of first order
   have been observed in Ag4Mn3O8 by means of in-situ powder diffraction
   and by differential scanning calorimetry. At a temperature of T = 477
   K, Ag4Mn3O8 undergoes a structural phase transition from the room
   temperature phase in space group P3(1)21 to a phase in space group R32,
   and at T = 689 K a second phase transition to a structure in space
   group P4(3)32 occurs. Whilst the Mn3O8 framework does not change
   significantly upon heating, rearrangements of the silver atoms, located
   in the cavities of the framework, were found to be the driving force
   behind the transitions. The structural chances with increasing
   temperature proceed along a path of minimal group-supergroup relations
   between the respective space groups.


Pan, ZG   Cheung, EY   Harris, KDM   Constable, EC   Housecroft, CE
A case study in direct-space structure determination from powder X-ray
   diffraction data: Finding the hydrate structure of an organic molecule
   with significant conformational flexibility
CRYSTAL GROWTH & DESIGN 5, 2005, 2084-2090.
The structure of the monohydrate crystalline phase of
   3,5-bis((3,4,5-trimethoxybenzyl)oxy)benzyl alcohol has been determined
   directly from powder X-ray diffraction data using the direct-space
   genetic algorithm technique for structure solution followed by Rietveld
   refinement. This work raises several issues of a general nature
   concerning the assessment of results obtained in the structure
   determination of organic molecular solids from powder X-ray diffraction
   data and serves as a case study that may find wider relevance in this


Okudera, H   Dinnebier, RE   Simon, A
The crystal structure of gamma-P-4, a low temperature modification of
   white phosphorus
The crystal structure of gamma-P-4, one of three modifications hitherto
   reported on white phosphorus, was determined from X-ray powder
   diffraction data collected at T = 123 K on a Guinier-Simon camera
   equipped with a cold gas blower and an image plate detector.
   Crystallographic data at T = 123 K are: space group C2/m, a = 9.1709(5)
   angstrom, b 8.3385(5) angstrom, c = 5.4336(2) angstrom, and beta =
   90.311(3)degrees, V 415.51(6) angstrom(3), Z = 4. The crystal structure
   Of gamma-P4 was solved by the method of simulated annealing. The
   subsequent Rietveld refinement in the range 12 degrees < 20 < 92
   degrees employing rigid-body constraints on the P-4 molecule converged
   at R-p = 3.8, wR(p) = 5.0, and R-F(2) = 14.0%. The asymmetric unit Of
   gamma-P-4 contains three P atoms; two P atoms in a molecule are related
   by a mirror plane which bisects the molecule. The centers of gravity of
   these P-4 molecules show a distorted body-centered cubic arrangement.
   The four apices of the P-4 tetrahedron point to the largest possible
   voids formed by neighbor molecules. The difference to the crystal
   structures of SiF4 and GeF4 with an exact bcc arrangement of
   tetrahedral molecules is discussed as well as, in terms of layer
   stackings, the similarity of the structures of gamma- and beta-P-4.


Ryabova, SY   Rastorgueva, NA   Sonneveld, EJ   Peschar, R
   Schenk, H   Tafeenko, VA   Aslanov, LA   Chernyshev, VV
Structural characterization of [1,4]diazepino[6,5-b]indoles by powder
As part of a systematic structural study of potentially
   pharmacologically active [1,4] diazepino[6,5-b] indoles, the crystal
   structures of nine compounds have been determined from laboratory
   powder diffraction data. The investigated compounds are:
   2-oxo-1-(4-nitrophenyl)- 1,2,3,6-tetrahydro[ 1,4] diazepino[ 6,5-b]
   indole-4-oxide, C17H12N4O4 (1a); 2-oxo-
   1-phenyl-1,2,3,6-tetrahydro[1,4] diazepino[6,5-b] indole-4-oxide,
   C17H13N3O2 (1b); 2-oxo-1-(4-ethoxyphenyl)-1,2,3,6-tetrahydro[ 1,4]
   diazepino[6,5-b] indole-4-oxide, C19H17N3O3( 1c); 2-oxo-
   1-(4-chlorophenyl)- 1,2,3,6- tetrahydro[ 1,4] diazepino[ 6,5-b]
   indole-4-oxide, C17H12N3O2Cl (1d); 2-oxo-1-(4-cyanophenyl)-
   1,2,3,6-tetrahydro[1,4] diazepino[6,5-b] indole-4-oxide, C18H12N4O2
   (1e); 6-methyl-2-oxo-1-phenyl-1,2,3,6-tetrahydro[ 1,4] diazepino[6,5-b]
   indole-4-oxide, C18H15N3O2 (1f); 2-formyl-3-[N'-(omega-chloracetyl)-
   N'-(4-nitrophenyl)] aminoindole, C17H12N3O4Cl (2a);
   2-formyl-3-[N'-(omega-chloracetyl)N'-( 4-nitrophenyl)] aminoindole
   solvate with toluene (2: 1), C17H12N3O4Cl  .  0.5C(7)H(8) (2as);
   2-formyl-3-[N'-(omega-chloracetyl)N'-( 4-cyanophenyl)] aminoindole,
   C18H12N3O2Cl (2e). Compounds ( 1a) -( 1f) crystallize in
   non-centrosymmetric triclinic, monoclinic and orthorhombic space
   groups. The three-dimensional structures of ( 1a) -( 1e) demonstrate
   identical intermolecular NH( indole)  .   .   .
   O<--N hydrogen bonds, which form linear chains of connected molecules.
   A comparison of the crystal structures ( 2a), ( 2e) and ( 2as) shows
   that the solvent used in the re-crystallization of ( 2a) and ( 2e),
   which are intermediates in the synthesis of ( 1a) and ( 1e), affects
   the intermolecular hydrogen-bond formation and, as a result, leads to
   essentially different yields of the goal products.

Stride, JA
Determination of the low-temperature structure of hexamethylbenzene
The low-temperature structure of hexamethylbenzene has been determined
   from neutron powder diffraction data and found to differ from the
   room-temperature phase predominantly by a translation of molecular
   planes to a form a cubic close-packed type structure. By performing
   measurements as a function of temperature, the role of thermally
   induced agitation of the molecular units in the first-order phase
   transition is clearly demonstrated.

Guillou, N   Livage, C   Chaigneau, J   Ferey, G
Structural investigation of the nickel 3-methylglutarate from powder
   diffraction demonstrating adaptability of the inorganic skeleton of
POWDER DIFFRACTION 20, 2005, 288-293.
Ni-20[(C6H8O4)(20)(H2O)(8)] .  33H(2)O, a new nickel(II)
   3-methylglutarate, was prepared hydrothermally (180 degrees C, 48 h,
   autogenous pressure) from a 1: 1.5:2:180 mixture of nickel (II)
   sulphate hexahydrate, 3-methylglutaric acid, sodium hydroxide, and
   water. It crystallizes in the cubic system (space group P4(3)32, Z=1)
   with a = 16.8488(5) angstrom and V=4783.1(4) angstrom(3). Its structure
   was solved from conventional X-ray powder diffraction data. It presents
   a three-dimensional network of edge-sharing nickel octahedra, lined by
   deprotonated organic anions. This remarkable oxide network with
   corrugated 20-membered rings is constructed from homochiral helices.
   The rings intersect each other to generate large crossing channels full
   of water along [111].


Fossdal, A   Brinks, HW   Fichtner, M   Hauback, BC
Determination of the crystal structure of Mg(AlH4)(2)by combined X-ray
   and neutron diffraction
The structure of magnesium alanate, Mg(AlH4)(2), has been examined in
   detail by combined powder synchrotron X-ray and neutron diffraction.
   The space group is confirmed to be P (3) over barm 1 with unit cell
   dimensions of a = 5.2084(3) Angstrom and c = 5.8392(5) Angstrom at 8 K,
   a = 5.20309(12) Angstrom and c = 5.8400(2) Angstrom at 111 K and a =
   5.1949(2) Angstrom and c = 5.8537(2) Angstrom at 295 K. The structure
   consists of isolated and slightly distorted AlH4- tetrahedra that are
   connected via six-coordinated Mg atoms in a distorted octahedral
   geometry, resulting in a sheet-like structure along the
   crystallographic c-axis. The distortion of the AlH4- tetrahedra
   decreases with increasing temperature, whereas, the opposite is the
   case for the MgH6 octahedra. The Al-H distances are 1.606(10)-1.634(4)
   Angstrom, 1.602(10)-1.682(3) Angstrom and 1.561(12)-1.672(4) Angstrom
   at 8, 111 and 295 K, respectively.


Brandel, V   Clavier, N   Dacheux, N
Synthesis and characterization of uranium(IV)
   phosphate-hydrogenphosphate hydrate and cerium(IV)
   phosphate-hydrogenphosphate hydrate
A new uranium (IV) phosphate of proposed formula
   U-2(PO4)(2)(HPO4H2O)-H-., i.e. uranium phosphate-hydrogen phosphate
   hydrate (UPHPH), was synthesized in autoclave and/or in
   polytetrafluoroethylene closed containers at 150 degrees C by three
   ways: from uranium (IV) hydrochloric Solution and phosphoric acid, from
   uranium dioxide and phosphoric acid and by transformation Of the
   uranium hydrogenphosphate hydrate U(HPO4)(2)(.)nH(2)O. The new product
   appears similar to the previously published thorium
   phosphate-hydrogenphosphate hydrate Th-2(PO4)(2)(HPO4H2O)-H-. (TPHPH).
   From preliminary studies, it was found that UPHPH crystallizes in
   monoclinic system (a = 2.1148(7) nm, b = 0.6611(2) nm, c = 0.6990(3)
   nm, beta = 91.67(3)degrees and V = 0.9768(10) nm(3)). Heated under
   inert atmosphere, this compound is decomposed above 400 degrees C into
   uranium phosphate-triphosphate U-2(PO4)P3O10, uranium diphosphate
   alpha-UP2O7 and diuranium oxide phosphate U2O(PO4)(2). Crystallized
   cerium (IV) phosphate-hydrogenphosphate hydrate
   Ce-2(PO4)(2)(HPO4H2O)-H-. (CePHPH) was also synthesized from
   (NH4)(2)Ce(NO3)(6) and phosphoric acid Solutions by the same method
   (inonoclinic system: a = 2.1045(5) nm, b = 0.6561(2) nm, c = 0.6949(2)
   nm, beta = 91.98(1)degrees and V = 0.9588(9) nm(3)). When heating above
   600 degrees C. cerium (IV) is reduced into Ce (III) and forms a mixture
   of CePO4 (monazite structure) and CeP3O9.


Shpanchenko, RV   Lapshina, OA   Antipov, EV   Hadermann, J
   Kaul, EE   Geibel, C
New lead vanadium phosphate with langbeinite-type structure:
The new lead vanadium phosphate Pb1.5V2(PO4)(3) was synthesized by
   solid state reaction and characterized by X-ray powder diffraction,
   electron microscopy, and magnetic susceptibility measurements. The
   crystal structure of Pb1.5V2(PO4)(3) (a=9.78182(8) angstrom, S.G.
   P2(1)3, Z=4) was determined from X-ray powder diffraction data and
   belongs to the langbeinite-type structures. It is formed by
   corner-linked V3+O6 octahedra and tetrahedral phosphate groups
   resulting in a three-dimensional framework. The lead atoms are situated
   in the structure interstices and only partially occupy their positions.
   An electron microscopy study confirmed the structure solution. Magnetic
   susceptibility measurements revealed Curie-Weiss (CW) behavior for
   Pb1.5V2(PO4)(3) at high temperature whereas at around 14 K an abrupt
   increase on the susceptibility was observed.


Redman-Furey, N   Dicks, M   Bigalow-Kern, A   Cambron, RT
   Lubey, G   Lester, C   Vaughn, D
Structural and analytical characterization of three hydrates and an
   anhydrate form of risedronate
Four hydration states are reported for Risedronate monosodium. A
   single-crystal X-ray structure determination is provided as proof of
   assignment for the monohydrate, hemi-pentahydrate, and variable hydrate
   forms. The structure provided for the anhydrate form was determined
   through simulating annealing calculations and subsequent Reitveld
   refinement of a high-quality X-ray powder diffraction patterns
   Favorable comparisons of experimentally obtained X-ray powder patterns
   are made to those generated from the single crystal data.
   Characteristic infrared, Raman, and NMR spectra are provided and
   discussed for each form as are thermal analysis profiles. In addition,
   photomicrographs are provided for each of the forms isolated for this
   study. The hemi-pentahydrate is demonstrated to be the equilibrium form
   at room temperature and 37 degrees C, in the presence of water.


Karau, FW   Schnick, W
High-pressure synthesis and X-ray powder structure determination of the
   nitridophosphate BaP2N4
The novel nitridophosphate BaP2N4 was obtained by means of
   high-pressure high-temperature synthesis utilizing the multianvil
   technique (8 GPa, 1400degreesC. The [PN2](-) network is isoelectronic
   with silica. The structure was solved from synchrotron powder data by a
   combination of direct methods and difference FOURIER synthesis and
   refined using the RIETVELD method (BaP2N4,Pa $$(3) over bar, Z= 12, a =
   10.22992(2) Angstrom). BaP2N4 is isotypic with BaGa2S4, BaAl2S4 and the
   high-pressure phase of CaB2O4. The (31)p solid-state NMR yielded a
   single sharp resonance at 0.4ppm.


Chemnitzer, R   Auffermann, G   Tobbens, DM   Kniep, R
(Sr2N)H: On the redox-intercalation of hydrogen into Sr2N
Strontium-nitride-hydride is obtained as brown-yellow single phase
   powder by reaction of strontium-subnitride (Sr2N) with hydrogen (200
   bar, 620 K) and subsequent treatment under vacuum (10(-6) bar, 870 K).
   The structure determination was carried out by a combination of X-ray
   and neutron diffraction experiments on a deuterated sample. The
   elemental composition of the ternary compound was confirmed by means of
   chemical analyses. (Sr2N)D crystallizes in the space group R (3) over
   barm with a = 381.91(2) pm and c = 1887.61(2) pm. Strontium (Sr2+) in
   the crystal structure of (Sr2N)D is arranged with an only slightly
   distorted ccp-motif. Nitrogen (N3-) and deuterium (D-) occupy the
   octahedral voids of the Sr2+ matrix in an ordered manner resulting in
   an alternating sequence of layers (anti-alpha-NaFeO2-type structure).


Argyriou, DN   Radaelli, PG   Milne, CJ   Aliouane, N   Chapon, LC
   Chemseddine, A   Veira, J   Cox, S   Mathur, ND   Midgley, PA
Crystal structure of the superconducting layered cobaltate NaxCoO2
    .  yD(2)O
We have used electron diffraction and neutron powder diffraction to
   elucidate the structural properties of superconducting
   Na(x)CoO(2)(.)yD(2)O over a wide compositional range. Our measurements
   show that superconducting samples exhibit a number of supercells
   ranging from (1)/(3)a* to (1)/(15)a*, but the predominant modulation,
   observed also in the neutron data, is a double hexagonal cell with
   dimensions 2a x 2a x c. Rielveld analysis reveals that D2O is inserted
   between CoO2 sheets to form a layered network of NaO6 triangular
   prisms. Our model removes the need to invoke a 5 K superconducting
   point compound and suggests that a solid solution of Na is possible
   within a relatively constant amount of water y.


Vicente, J   Arcas, A   Fernandez-Hernandez, JM   Sironi, A   Masciocchi, N
An unprecedented process involving normal and redox transmetallation
   reactions between Hg and Pt affording the unexpected
   K[Pt-2{CH2C(O)Me}(6)(mu-Cl)(3)] complex: the key role of X-ray powder
   diffraction in unravelling its nature and structure
CHEMICAL COMMUNICATIONS iss 10, 2005, 1267-1269.
Hg{CH2C(O) Me}(2)] reacts with K[PtCl3(CH2LCH2)] (2 : 1 molar ratio) to
   give K[Pt-2{CH2C(O) Me}(6)(mu- Cl)(3)] ( 1); the intermediate
   [Pt{CH2C(O) Me} Cl-2(CH2=CH2)](-) has been detected in solution and
   isolated as a Me4N+ salt; the process occurs through successive normal
   and redox transmetallation reactions and an ab initio X-ray powder
   diffraction study of 1 has proven to be essential to establish its


Wu, L   Chen, XL   Li, XZ   Dai, L   Xu, YP   Zhao, M
Synthesis and ab initio X-ray powder diffraction structure of the new
   alkali and alkali earth metal borate NaCa(BO3)
A sodium calcium borate, NaCaBO3, has been synthesized by the
   solid-state reaction method and the structure solved from X-ray powder
   diffraction data. The compound crystallizes in space group Pmmn and has
   a desired structure type containing isolated planar BO33- anions. Mixed
   occupancy is found to exist in the Ca site, with partial replacement by
   Na. One Ca/Na mixed atom and one Na atom are at sites with mm2
   symmetry, and a second Ca/Na mixed atom, an Na atom, two B and two O
   atoms are on mirror planes.


Dova, E   Peschar, R   Takata, M   Nishibori, E   Schenk, H
   Stassen, AF   Haasnoot, JG
Low-spin state structure of [Fe(chloroethyltetrazole)(6)] (BF4)(2)
   obtained from synchrotron powder diffraction data
The complex [Fe(teec)(6)]-(BF4)(2) (teec = chloroethyltetrazole) shows
   a two-step complete spin-crossover transition in the temperature range
   300-90 K. Time-resolved synchrotron powder diffraction experiments have
   been carried out in this temperature range, and crystal. structure
   models have been obtained from the powder patterns by using the
   parallel tempering technique. Of these models, the low-spin state
   structure at 90 K has been refined completely with Rietveld refinement.
   Its structural characteristics are discussed in relation to the
   high-spin state model and other spin-crossover compounds. The complex
   shows a remarkable anisotropic unit-cell parameter contraction that is
   dependent on the applied cooling rate. In addition, the possible
   important implications for the interpretation of spin-crossover
   behavior in terms of structural changes are discussed.


Liu, XH   Wankeu, MA   Lucken, H   Dronskowski, R
A novel method for synthesizing crystalline copper carbodiimide, CuNCN.
   Structure determination by X-ray rietveld refinement
Well-crystallized copper carbodiimide, CuNCN, was synthesized by the
   slow oxidation of a copper(l) cyanamide precursor under aqueous
   conditions. The X-ray powder data evidence the orthorhombic system and
   space group Cmcm with a = 2.9921(1), b = 6.1782(1), c = 9.4003(2)
   angstrom, V = 173.769(5) angstrom(3) and Z = 4. There is a strongly
   distorted octahedral Cu2+ coordination reflecting a typical first-order
   Jahn-Teller effect, with interatomic distances of 4 x Cu-N = 2.001(2)
   angstrom and 2 x Cu-N = 2.613(3) angstrom; the NCN2- unit adopts the
   carbodiimide shape with C-N = 1.227(4) A. Despite the formal d(9)
   electron count of Cu2+, CuNCN exhibits a small temperature-independent
   paramagnetism and is likely to be a metallic conductor.


Xu, HW   Navrotsky, A   Nyman, M   Nenoff, TM
Thermochemistry of framework titanosilicate A(2)TiSi(6)O(15) (A = K,
   Rb, Cs)
A new family of framework titanosilicates, A(2)TiSi(6)O(15) (A = K, Rb,
   Cs) (space group Cc), has recently been synthesized using the
   hydrothermal method. This group of phases can potentially be utilized
   for storage of radioactive elements, particularly Cs-137, due to its
   high stability under electron radiation and chemical leaching. Here, we
   report the syntheses and structures of two intermediate members in the
   series: KRbTiSi6O15 and RbCsTiSi6O15. Rietveld analysis of powder
   synchrotron X-ray diffraction data reveals that they adopt the same
   framework topology as the end-members, with no apparent Rb/K or Rb/Cs
   ordering. To study energetics of the solid solution series,
   high-temperature drop-solution calorimetry using molten 2PbO  .
   B2O3 as the solvent at 975 K has been performed for the end-members and
   intermediate phases. As the size of the alkali cation increases, the
   measured enthalpies of formation from the constituent oxides (Delta
   H-f,ox(0)) and from the elements (Delta H-f,el(0)) become more
   exothermic, suggesting that this framework structure favors the cation
   in the sequence Cs+, Rb+, and K+. This trend is consistent with the
   higher melting temperatures of A(2)TiSi(6)O(15) phases with increase in
   the alkali cation size.


Dikarev, EV   Li, B   Chernyshev, VV   Shpanchenko, RV   Petrukhina, MA
Coordination polymers formed in solution and in solvent-free
   environment. Structural transformation due to interstitial solvent
   removal revealed by X-ray powder diffraction
CHEMICAL COMMUNICATIONS iss 26, 2005, 3274-3276.
The crystal-to-powder transformation induced by solvent removal has
   been examined through a direct comparison of the structures of the
   solvated and the unsolvated coordination products determined by single
   crystal and powder X-ray diffraction, respectively.


Shrivastava, OP   Kumar, N   Sharma, IB
Synthesis, characterization and structural refinement of
   polycrystalline uranium substituted zirconolite
Ceramic precursors of Zirconolite (CaZrTi2O7) family have a remarkable
   property of substitution on Zr4+ cationic sites. This makes them
   potential material for nuclear waste management in 'synroc' technology.
   In order to simulate the mechanism of partial substitution of zirconium
   by tetravalent actinides, a solid phase of composition
   CaZr0.95U0.05Ti2O7 has been synthesized through ceramic route by taking
   calculated quantities of oxides of Ca, Ti and nitrates of uranium and
   zirconium respectively. Solid state synthesis has been carried out by
   repeated pelletizing and sintering the finely powdered oxide mixture in
   a muffle furnace at 1050 degrees C. The polycrystalline solid phase has
   been characterized by its typical powder diffraction pattern. Step
   analysis data has been used for ab initio calculation of structural
   parameters. The SEM and EDAX analysis also confirm that zirconolite
   acts as a host material for uranium. The powder diffraction data of
   3500 points between 2 theta = 10 - 80 degrees has been analysed by GSAS
   ( general structure analysis system) software to obtain the best fit of
   the observed data points. The uranium substituted zirconolite
   crystallizes in monoclinic symmetry with space group C2/c (# 15). The
   following unit cell parameters have been calculated: a = 12.4883( 15),
   b = 7.2448( 5), c = 11.3973( 10) and beta = 100.615( 9)degrees. The
   calculated and observed values of the intensities, lattice parameters
   and density measurement shows good agreement. The Rietveld analysis and
   GSAS based calculations for bond distance Ti-O, Ca-O, Zr-O, and O-M-O
   bond angles have been made. The structure was refined to satisfactory
   completion. The and Rp and Rwp are found to be 7.48 and 9.74 %

2005-136 ???

Zhu, ZM   Andelman, T   Yin, M   Chen, TL   Ehrlich, SN
   O'Brien, SP   Osgood, RM
Synchrotron x-ray scattering of ZnO nanorods: Periodic ordering and
   lattice size
We demonstrate that synchrotron x-ray powder diffraction (XRD) is a
   powerful technique for Studying the structure and self-organization of
   zinc-oxide nanostructures. Zinc-oxide nanorods were prepared by a
   solution-growth method that resulted ill uniform nanorods with 2-nm
   diameter and lengths in the range 10-50 nm. These nanorods were
   structurally characterized by a combination of small-angle and
   wide-angle synchrotron XRD and transmission electron microscopy (TEM).
   Small-angle XRD and TEM were used to investigate nanorod self-assembly
   and the influence of surfactant/precursor ratio oil self-assembly.
   Wide-angle XRD was used to study the evolution of nanorod growth as a
   function of synthesis time and surfactant/precursor ratio.


Orlova, MP   Kitaev, DB   Spiridonova, ML   Zubkova, NV
   Kabalov, YK   Orlova, AI
Structure refinement of cadmium cerium(IV) phosphate Cd0.5Ce2(PO4)(3)
Cadmium cerium orthophosphate Cd0.5Ce2(PO4)(3) is synthesized by
   precipitation from aqueous solutions. The structure refinement from
   powder X-ray diffraction data is preceded by the sample preparation and
   structure solution. The refinement is carried out by the Rietveld
   method (ADP-2 diffractometer, Cu-K alpha radiation, Ni filter, 15
   degrees < 2 theta < 120 degrees, 2 theta-scan step 0.02 degrees,
   counting time 10 s per step). All calculations are carried out using
   the WYRIET program (version 3.3) within the sp. gr. P2(1)/n. The
   structure is refined with anisotropic displacement parameters for
   cations and isotropic displacement parameters for oxygen atoms.


Tobbens, DM   Kahlenberg, V   Kaindl, R
Characterization and ab initio XRPD structure determination of a novel
   silicate with vierer single chains: The crystal structure of NaYSi2O6
INORGANIC CHEMISTRY 44, 2005, 9554-9560.
The crystal structure of a sodium yttrium silicate with composition
   NaYSi2O6 has been determined from laboratory X-ray powder diffraction
   data by simulated annealing, and has been subsequently refined with the
   Rietveld technique. The compound is monoclinic with space group P2(1)/c
   and unit cell parameters of a = 5.40787(2) angstrom, b = 13.69784(5) A,
   c = 7.58431(3) angstrom, and beta = 109.9140(3)degrees at 23.5 degrees
   C (Z = 4). The structure was found to be a single-chain silicate with a
   chain periodicity of four. The two symmetry dependent [Si4O12] chains
   in the unit cell are parallel to c. A prominent feature is the strong
   folding of the crankshaft-like chains within the b,c-plane resulting in
   intrachain Si-Si-Si angles close to 90 degrees. The coordination of the
   Y3+ ions by O2- is 7-fold in the form of slightly irregular pentagonal
   bipyramids, with oxygen atoms from four different chains contributing
   to the coordination polyhedron. Na+ ions are irregularly coordinated by
   10 oxygens from two neighboring chains. No disorder of Na+ and Y3+
   between the two nontetrahedral cation sites could be observed.
   Furthermore, micro-Raman spectra have been obtained from the
   polycrystalline material.


Parfitt, DC   Keen, DA   Hull, S   Crichton, WA   Mezouar, M
   Wilson, M   Madden, PA
High-pressure forms of lithium sulphate: Structural determination and
   computer simulation
PHYSICAL REVIEW B 72, 2005, 054121.
Powder x-ray diffraction has been performed on lithium sulphate,
   Li2SO4, in the temperature range 300 to 1000 K and at pressures up to
   7.5 GPa. The ambient pressure beta phase appears stable up to 3 GPa,
   whereupon a slow transformation begins into a new phase, delta-Li2SO4.
   This phase is characterized by broad, very low intensity Bragg peaks.
   Above 7 GPa and with slight heating, another phase, epsilon-Li2SO4, is
   formed which shows sharp Bragg peaks. Rietveld refinement of the
   structure of the epsilon phase has shown it to be isostructural to the
   high-temperature phase III of Na2SO4. Molecular dynamics simulations of
   the epsilon phase using an established potential indicate disordering
   of the lithium ions and rotations of the sulphate groups at high
   temperature, but not at a level approaching the extreme disordering
   shown in the superionic alpha form of Li2SO4.


Romer, SR   Schnick, W
Synthesis and crystal structure determination by X-ray powder
   diffraction of nickel tetrametaphosphimate octahydrate
   Ni-2(PO2NH)(4) .  8 H2O
Ni(PO2NH)(4)  .  8H(2)O is isotypic with M-2(PO2NH)(4) center
   dot 8 H2O (M = Mg, Mn, Co, Zn) and crystallizes in the space group
   P2(1)/c, Z = 2. with a = 641.25(l), b = 1041.42(l), c 1278.18(2) pm and
   beta = 104.243(l)degrees. The structure is composed of Ni2+ and
   (PO2NH)(4)(4-) ions as well as crystal water molecules. The P4N4 rings
   of the (PO2NH)(4)(4-) ions exhibit a slightly distorted chair-2
   conformation, which has been described by torsion angles, displacement
   asymmetry parameters and Puckering parameters. The tetrametaphosphimate
   anions are connected forming layers. These layers are linked solely by
   hydrogen bonds, forming a three-dimensional network.


Brodski, V   Peschar, R   Schenk, H   Brinkmann, A   Bloemberg, TG
   van Eck, ERH   Kentgens, APM
Structural analysis of a melaminium polyphosphate from X-ray powder
   diffraction and solid-state NMR data
JOURNAL OF PHYSICAL CHEMISTRY B 109, 2005, 13529-13537.
The crystal structure of the environmentally friendly flame retardant
   melaminium polyphosphate (MPoly)
   (2,4,6-triamino-1,3,5-triazinium-PO3)(n) was determined by a
   direct-space global optimization technique from X-ray powder
   diffraction data. Solid-state NMR was used to corroborate the proposed
   hydrogen-bonding model and to determine the average degree of
   polymerization (n > 100). An analysis of the crystal structure of MPoly
   reveals aspects of molecular geometry and packing that are
   characteristic for melamine-containing compounds and polyphosphate
   salts. A comparison of MPoly with the crystal structures of its
   precursors melaminium orthophosphate (MP) and melaminium
   dihydrogenpyrophosphate (MPy) provides insight in the mechanism of the
   endothermic dehydration processes that takes place in the reaction path
   MP -> MPy -> MPoly. Solid-state NMR characterization of various samples
   of the same batch showed inhomogeneities in the MPoly composition.
   Various quantities of orthophosphates were found, which cannot be
   assigned to be MP.


Hoyos, D   Paillaud, JL   Simon-Masseron, A   Guth, JL
Synthesis, characterization and structure determination of a
   three-dimensional hydrated potassium zinc divanadate:
   K[Zn2.5V2O7(OH)2] .  H2O
SOLID STATE SCIENCES 7, 2005, 616-621.
K[Zn2.5V2O7(OH)(2)] .  H2O was obtained by hydrothermal
   synthesis at 170 degrees C from a gel with the molar composition 1
   V2O5; 1 ZnCl2; 4 KOH; 228 H2O. The solid crystallizes in the
   orthorhombic system, with the space group Pnnm (58) and with the
   unit-cell parameters a = 14.5493(12) angstrom, b = 10.1685(9) angstrom,
   c = 6.0668(5) angstrom. The structure was determined from the powder
   XRD pattern by an "ab initio" method using the EXPO software and
   refined with the GSAS Rietveld refinement software. The structure can
   be described as formed from an interrupted and lacunary oxohydroxo zinc
   layers bridged by divanadate into a three-dimensional framework. The
   potassium cations and the water molecules occupy the channels between
   the bridged layers. The thermal stability, studied with the use of TGA
   and XRD, shows that the compound remains crystalline during the
   dehydration which occurs between room temperature and 210 degrees C.


Shankland, K   Kennedy, AR   David, WIF
Polymorphism in tetra-aryl biphenyl diamine hole transport materials:
   resolving the conflicting literature on N, N '-diphenyl-N, N
   '-bis(3,3'-methylphenyl)-1(1,1 '-biphenyl)1-4,4 '-diamine by
   high-resolution powder diffraction
The existence of a second polymorphic form of the hole transport
   material N,N'-diphenyl-N,N'-bis(3,3'-methylphenyl)-[(1,
   1'-biphenyl)]-4,4'-diamine has been confirmed using both Pawley and
   Rietveld refinement of structural information against high-resolution
   synchrotron X-ray powder diffraction data.


Mellot-Draznieks, C   Serre, C   Surble, S   Audebrand, N   Ferey, G
Very large swelling in hybrid frameworks: A combined computational and
   powder diffraction study
Using a combination of simulations and powder diffraction, we report
   here the study of the very large swelling of a three-dimensional
   nanoporous iron(III) carboxylate (MIL-88) which exhibits almost a
   reversible doubling (similar to 85%) of its cell volume while fully
   retaining its open-framework topology. The crystal structure of the
   open form of MIL-88 has been successfully refined and indicates that
   atomic displacements larger than 4 angstrom are observed when water or
   various alcohols are adsorbed in the porous structure, revealing an
   unusually flexible crystallized framework. X-ray thermodiffractometry
   shows that only a displacive transition occurs during the swelling
   phenomenon, ruling out any bond breaking.


Ferey, G   Mellot-Draznieks, C   Serre, C   Millange, F
   Dutour, J   Surble, S   Margiolaki, I
A chromium terephthalate-based solid with unusually large pore volumes
   and surface area
SCIENCE 309, 2005, 2040-2042.


Warrender, SJ   Wright, PA   Zhou, W   Lightfoot, P   Camblor, MA
   Shin, CH   Kim, DJ   Hong, SB
Structure of the novel large pore allosilicate TNU-7
   AND B 158, 2005, 89-96.
The Structure of a novel large pore gallosilicate zcolite, TNU-7, has
   been refined from X-ray powder diffraction data. The silicate framework
   is built Lip from two different types of layer which are shown by X-ray
   and electron diffraction to be arranged in a fully ordered way. This
   gives rise to 12-MR pores and asymmetric cation distributions. TNU-7 is
   prepared hydrothemally over a very narrow compositional range and only
   in the presence of Ga. Other zeolitic phases crystallise at lower and
   higher Ga contents confirming the unique structure-directing ability of
   this element. The location of ion exchanged Cs+ and Sr2+ cations in
   TNU-7 has been Studied by high resolution X-ray powder diffraction.

Warrender, SJ   Wright, PA   Zhou, WZ   Lightfoot, P   Camblor, MA
   Shin, CH   Kim, DJ   Hong, SB
TNU-7: A large-pore gallosilicate zeolite constructed of strictly
   alternating MOR and MAZ layers
The structure solution of TNU-7 (Taejon National University number 7),
   a large-pore gallosilicate zeolite constructed of strictly alternating
   MOR and MAZ layers, is presented. This "boundary phase" zeolite was
   synthesized without recourse to organic additives in a crystallization
   field surrounded by those of the structurally related MAZ and MOR


Snedden, A   Charkin, DO   Dolgikh, VA   Lightfoot, P
Crystal structure of the 'mixed-layer' Aurivillius phase Bi5TiNbWO15
The crystal structure of the Aurivillius phase Bi5TiNbWO15 has been
   analyzed in detail using powder X-ray and neutron diffraction. The
   structure can be described as a regular intergrowth of alternating
   single and double perovskite-like layers sandwiched between
   fluorite-like bismuth oxide layers, such that the layer sequence is ...
   [WO4]-[Bi2O2]-[BiTiNbO7]-[Bi2O2] .... There is complete ordering of
   tungsten within the B sites of the single perovskite layer, so that the
   structure can be described as a direct intergrowth of the 'component'
   Aurivillius phases B2WO6 and Bi3TiNbO9. At 25degreesC the structure
   adopts the polar orthorhombic space group 12cm, a = 5.4231(2) Angstrom,
   b = 5.4027(2) Angstrom, c = 41.744(1)Angstrom.


Jacob, DS   Makhluf, S   Brukental, I   Lavi, R   Solovyov, LA   Felner, I
   Nowik, I   Persky, R   Gottlieb, HE   Gedanken, A
Sonochemical synthesis and characterization of Ni(C4H6N2)(6)(PF6)(2),
   Fe(C4H6N2)(6)(BF4)(2), and Ni(C4H6N2)(6)(BF4)(2) in
   1-butyl-3-methylimidazole with hexafluorophosphate and tetrafluoroborate
This paper reports on the inorganic sonochemical synthesis of
   crystalline Ni(C4H6N2)(6)(PF6)(2), Fe(C4H6N2)(6)(BF4)(2), and
   Ni(C4H6N2)(6)(BF4)(2) in the ionic liquids, 1-butyl-3-methylimidazolium
   hexafluorophosphate (BMI)(+)(PF6)(-) and 1-butyl-3-methylimidazolium
   tetrafluoroborate (BMI)(+)(BF4)(-). The structures of the compounds
   were determined and refined by using powder X-ray diffraction methods.
   The salts crystallize in the trigonal P (3) over bar space group. IR,
   Raman and F-19 NMR spectroscopic studies confirm that the PF6- and BF4-
   anions are not bonded to the metal cations. Magnetic measurements
   reveal the paramagnetic nature of the complexes. Mossbauer
   investigations show that the iron atom in Fe(C4H6N2)(6)(BF4)(2) is in
   the oxidation +2 state. The broad EPR signals, which reflect the
   octahedral symmetry of the nickel complexes, were measured for
   Ni(C4H6N2)(6)(PF6)(2) and Ni(C4H6N2)(6)(BF4)(2).


Body, M   Silly, G   Legein, C   Buzare, JY   Calvayrac, F   Blaha, P
Structural investigations of beta-CaAlF5 by coupling powder XRD, NMR,
   EPR and spectroscopic parameter calculations
beta-CaAlF5 was synthesized by solid-state reaction. The precise
   structure was refined from X-ray powder diffraction data in the
   monoclinic space group P2(1)/c with lattice constants a = 5.3361
   angstrom, b = 9.8298 angstrom, c = 7.3271 angstrom, and beta = 109.91
   degrees (Z = 4). The structure exhibits isolated chains of AlF63-
   octahedra sharing opposite corners. F-19 and Al-27 solid state NMR
   spectra were recorded Using MAS and SATRAS techniques. An EPR spectrum
   was recorded for beta-CaAlF5:Cr3+. The experimental spectra were
   simulated in order to extract the NMR and EPR parameter values. Five
   fluorine sites and one low symmetry aluminium site were found in
   agreement with the refined structure.
   These parameters were calculated using empirical and ab-initio methods.
   The agreement obtained between the calculated F-19 chemical shift
   values, Al-27 quadrupolar parameters, Cr3+ EPR fine structure
   parameters and the experimental results demonstrates the
   complementarity of XRD, magnetic resonance experiments and theoretical


Carvajal, JJ   Parreu, I   Sole, R   Solans, X   Diaz, F   Aguilo, M
Growth and structural characterization of Rb3Yb2(PO4)(3): A new
   material for laser and nonlinear optical applications
CHEMISTRY OF MATERIALS 17, 2005, 6746-6754.
We report the synthesis of a new stoichiometric Yb compound,
   Rb3Yb2(PO4)(3), by high-temperature solution methods. This is the first
   material of the A(3)(I)B(2)(III)((XO4)-O-V)(3) family containing a
   lanthanide element and the only one that shows optical activity. We
   resolved the structure of Rb3Yb2(PO4)(3), which crystallize in the
   cubic system, space group of symmetry I2(I)3 (a = 16.8700(10) angstrom,
   Z = 16). and studied its evolution with the temperature. The thermal
   expansion coefficient of Rb3Yb2(PO4)(3) is alpha = 8.94 x 10(-6) K-1.
   This compound melts incongruently at 1450 K. The second-harmonic
   generation efficiency of the Rb3Yb2-(PO4)(3), although limited as a
   result of the crystal not presenting birefringence, was at least
   similar to that of potassium dihydrogen phosphate.


Casellas, N   Gamez, P   Reedijk, J   Mutikainen, I   Turpeinen, U
   Masciocchi, N   Galli, S   Sironi, A
Moisture-triggered 1,3,5-triazine-based cull molecular switch: A
   combined X-ray single-crystal and powder diffraction study
INORGANIC CHEMISTRY 44, 2005, 7918-7924.
A solvothermal synthetic procedure has been exploited to prepare the
   new [Cu3L(NO3)(6)](n) coordination polymer (1) by reaction of the
   ligand (opytrizediam Q with copper(II) nitrate. 1 has been structurally
   characterized by means of the conventional X-ray single-crystal
   diffraction technique. It crystallizes in the monoclinic C2/c space
   group with a = 16.830(3), b = 20.701(4), c = 18.170(4) angstrom, beta =
   113.26(3)degrees, V= 5816(2) angstrom(3), Z = 4. 1 consists of
   trinuclear Cu3L(NO3)(5) units connected by means of a nitrato-O,O'
   bridge. The resulting chains are involved in weak interchain
   head-to-tail pi-pi stacking interactions. In the presence of moisture,
   1 is readily converted into the hydrated [Cu3L(NO3)(5)](NO3) .
   H2O form (2). This second phase, monoclinic P2(1)/c, consists of
   isolated [Cu3L(NO3)(5)](+) and (NO3)(-) ions which accommodate water
   molecules in the crystal lattice. These subtle chemical and structural
   modifications accompanying the moisture-triggered 1-to-2 transformation
   have been demonstrated through a X-ray powder diffraction study. A
   thermodiffractometric analysis has evidenced that this solid-to-solid
   transformation is fully reversible, i.e., thermally induced dehydration
   of 2 restores 1. The analysis of the temperature dependence of the
   magnetic susceptibility for 2 has revealed very weak ferromagnetic
   interactions, consistent with the large (CuCu)-Cu-... separation (ca.
   7.5 angstrom) in the trinuclear units.


AU Navarro, JAR   Barea, E   Galindo, MA   Salas, JM   Romero, MA
   Quiros, M   Masciocchi, N   Galli, S   Sironi, A   Lippert, B
Soft functional polynuclear coordination compounds containing
   pyrimidine bridges
In this account, we describe the use of simple pyrimidine derivatives
   in combination with metal ions to build highly structured molecular
   architectures containing functional nanoenvironments, cavities and
   surfaces that can interact with additional species. The supramolecular
   structure of these systems can be rationally controlled by metal
   fragment geometry, reaction conditions and presence of templating
   agents. Thus, the use of transition metals with low coordination
   numbers or blocked bonding positions in combination with pyrimidines
   (e.g. 2-hydroxypyrimidine, 4-hydroxypyrimidine,
   2,4-dihydroxypyrimidine, 2-aminopyrimidine) leads to the formation of
   either discrete assemblies, ID polymers or helixes. When metal ions
   with higher coordination possibilities are applied instead, 2D and 3D
   networks are generated. Some of the assemblies built in this way
   possess functional cavities, pores and surfaces that can interact with
   additional species by means of hydrophobic, electrostatic, H-bonding
   interactions and coordinative bonds to give rise to recognition
   processes. The latter range from molecular recognition in homogeneous
   phase as well as clathrate formation, to heterogeneous solid-gas and
   solid-liquid adsorption phenomena. It should be noted that these
   materials are not rigid but able to undergo guest-induced
   reorganisation processes even in the solid state. Finally, some of
   these materials also combine additional interesting magneto-optical
   properties. Thus, dual systems can be envisaged in which two or more of
   these properties are present in the same material.

Cingolani, A   Galli, S   Masciocchi, N   Pandolfo, L   Pettinari, C   Sironi, A
Sorption-desorption behavior of bispyrazolato-copper(II) 1D
   coordination polymers

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