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Re: [sdpd] V4+


>Where can I find Scattering coefficients for V+4and how to use those data 
>for the rietveld analysis? And what shall I do if the valance of vanadium 
>is between +4 and +5?

This seems to be possible :

In FullProf, use NSCAT < 0 (linear interpolation).

Pages 489 and 490 of the International Tables for Crystallography,
calculate the atomic scattering factor for V4+ as being the
average of V3+ and V5+. f(0) = 19.000, etc. This would
certainly be a fair approximation.

Enter the appropriate values at lines 8-1 and 8-2 (see the manual) :

Line 8-1 : NAM, DFP, DFPP,ITYM
Line 8-2 :
         or  a set of lines of the form : sin(Theta)/l - f
         The set is terminated by a line with -100 in first position.

Note(2): If you
         want a linear interpolation NSCAT must be negative and the
         list is given as:  1000.0*2sin(Theta)/L- f

Hum, not clear what to use here, sin(Theta)/lambda
or 1000.0*2sin(Theta)/lambda  ???

Best wishes,

Armel

PS - See the example file : c60a.pcr :
COMM Single crystal data of C60 (X-ray, 
MoKa)
! Current global Chi2 (Bragg contrib.) =      97.01
! Files => DAT-file: c60,  PCR-file: c60a
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor Opt Aut
    0   0   1   0   0  -1   0   0   0   0   0   0   0   0   1   0   0   0   1
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 NLI Prf Ins Rpa Sym Hkl Fou Sho Ana
    0   0   1   1   1   0   0   0   0   1   0   0   0   0   0   0   0
!
!NCY  Eps  R_at  R_an  R_pr  R_gl     Thmin       Step       Thmax    PSD 
  Sent0
   8  0.10  1.00  1.00  1.00  1.00     10.0000   0.100000    89.9000 
0.000   0.000
!
! Additional scattering factors for Pattern#  1
c60     0.00000    0.00000   0
    0.000      1.00000
   22.599      0.95840
   45.198      0.83990
   67.797      0.66190
   90.396      0.45010
  112.994      0.23400
  135.593      0.04170
  158.192     -0.10450
  180.791     -0.19150
  203.390     -0.21710
  225.989     -0.18930
  248.588     -0.12390
  271.186     -0.04140
  293.785      0.03790
  316.384      0.09720
  338.983      0.12610
  361.582      0.12220
  384.181      0.09030
  406.780      0.04080
  429.379     -0.01300
  451.977     -0.05840
  474.576     -0.08570
  497.175     -0.09030
  519.774     -0.07310
  542.373     -0.04010
  564.972     -0.00010
  587.571      0.03670
  610.169      0.06210
  632.768      0.07090
  655.367      0.06210
  677.966      0.03910
  700.565      0.00820
  723.164     -0.02280
  745.763     -0.04640
  768.362     -0.05750
  790.961     -0.05410
  813.559     -0.03790
  836.158     -0.01350
  858.757      0.01290
  881.356      0.03480
  903.955      0.04730
  926.554      0.04770
  949.153      0.03660
  971.751      0.01720
  994.350     -0.00550
1016.949     -0.02590
1039.548     -0.03910
1062.147     -0.04230
1084.746     -0.03510
1107.345     -0.01970
1129.943     -0.00010
1152.542      0.01870
1175.141      0.03220
1197.740      0.03750
1220.339      0.03340
1242.938      0.02140
1265.537      0.00460
   -100.0
!
        2    !Number of refined parameters
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg for Pattern#  1:    20.47
!-------------------------------------------------------------------------------
  C60 

!
!Nat Dis Ang Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth       ATZ    Nvk Npr More
    1   0   0 0.0 0.0 1.0   0   4   0   0   0         48.040   0   0   0
!
F m 3 m                  <--Space group symbol
!Atom Typ       X        Y        Z     Biso       Occ     In Fin N_t Spc 
/Codes
C    c60     0.00000  0.00000  0.00000  7.18223   1.00000   0   0   0    0
                 0.00     0.00     0.00    21.00      0.00
!  Scale Factors
!   Sc1        Sc2         Sc3         Sc4         Sc5         Sc6
    33.97       0.000       0.000       0.000       0.000       0.000
        11.00        0.00        0.00        0.00        0.00        0.00
!  Extinction Parameters
! 
Ext1       Ext2       Ext3       Ext4       Ext5       Ext6       Ext7 
Ext-Model
   0.000      0.000      0.000      0.000      0.000      0.000      0.000 
      0
        0.00       0.00       0.00       0.00       0.00       0.00       0.00
!     a          b         c        alpha      beta       gamma
   14.152000  14.152000  14.152000  90.000000  90.000000  90.000000
     0.00000    0.00000    0.00000    0.00000    0.00000    0.00000
! x-Lambda/2  +          Not yet used parameters
      0.00000     0.00000     0.00000     0.00000     0.00000
         0.00        0.00        0.00        0.00        0.00




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