UPPW-10
January 23, 2004
Problem :
ICDD 44-1791
C26H32F2O7 - Diflorasone diacetate
Wavelength 1.54178 A
Filter : monochromator
Mica used as internal standard
Ref : J. Bernstein & L. Zevin, Ben-Gurion University of the
Negev, Beer-Sheva, Israel, ICDD Grant-in-Aid (1993).
CAS #: 33564-36-7
Mwt : 494.53
Sample from Ciba-Geigy AG Postfach CH-4002 Bassel (Schweiz)
Search in the Cambridge Structural Database for C26H32F2O7 :
found fluorocinonide P212121, a = 14.169, b = 6.297, c = 28.097
V = 2506.9A**3, Z = 4
d intensities
9.2298 23
8.9729 88
7.7400 35
7.6093 100
6.9416 6
6.6803 17
6.0586 7
5.9773 65
5.8733 35
5.8048 22
5.5684 87
5.4768 17
5.4038 6
5.1318 39
4.6991 24
4.4205 16
4.2996 18
4.1369 3
3.8673 12
3.7867 12
3.6796 7
3.6567 7
3.6239 3
3.5366 11
3.2843 15
3.2048 7
3.1130 6
3.0514 3
3.0265 6
2.9564 9
2.9360 5
2.8908 3
2.8240 3
2.7314 4
2.6882 3
2.6551 2
RESULTS :
consensus on an orthorhombic cell with volume close to the
isoformula compound in the CSD database (~2500A**3).
Most probable cell(s) according to the Participants :
Program a b c alpha beta gamma V
M(20) F 20 Unindexed Zero Spacegroup
TREOR (NM) 15.260 13.876 11.740 90. 90. 90. 2486.0
M(20)= 14 F20 = 34 (0.01462, 41)
If allowance is made for one unindexed line amd one 'bad measurement' or typographic error
(9.2298 instead of 9.3298) for the first peak...
CRYSFIRE (RS) 13.892 15.253 11.750 90. 90. 90. 2489.8
M(19)=20 M(18)=25 P212121 ?
AUTOX (VZ) two phases suggested by using the multiphase indexing option:
phase 1 : 13.891 11.746 15.230 90. 90. 90. 2484.9 (main phase, 32 lines)
phase 2 : 9.233 9.233 8.027 90. 90. 90. 684.3 (secondary phase, 4 lines)
McMaille (ALB) 11.739 13.891 15.236 90. 90. 90. 2484.5
M(20)=19 F20 = 49 (0.0083, 49)
Results from NM (TREOR), Robin Shirley (CRYSFIRE), Victor Zlokazov (AUTOX) and Armel Le Bail (McMaille).
Plot by using WinPlotr on the McMaille results :
ZERO LAMBDA A B C ALPHA BETA GAMMA
-0.005 1.5418 11.7391 13.8913 15.2358 90.000 90.000 90.000
0.007 0.0000 0.0048 0.0061 0.0062 0.000 0.000 0.000
RECIPROCAL CELL : 0.08519 0.07199 0.06563 90.000 90.000 90.000
VOLUME (A**3) : 2484.512
H K L TH(OBS) TH-ZERO TH(CALC) DIFF.
1 1 0 9.862 9.858 9.864 -0.007
1 1 1 11.437 11.433 11.451 -0.018
0 0 2 11.634 11.630 11.616 0.014
0 2 0 12.757 12.753 12.745 0.008
0 1 2 13.258 13.254 13.255 -0.001
1 2 0 14.825 14.821 14.819 0.002
2 0 0 15.089 15.085 15.094 -0.009
1 1 2 15.268 15.264 15.261 0.002
1 2 1 15.920 15.916 15.926 -0.010
2 0 1 16.188 16.184 16.182 0.002
2 1 0 16.408 16.404 16.394 0.009
0 2 2 17.284 17.280 17.277 0.003
1 2 2 18.889 18.885 18.870 0.015
1 1 3 20.091 20.087 20.093 -0.006
2 2 1 20.662 20.658 20.651 0.006
2 2 2 23.001 22.997 23.018 -0.021
3 0 1 23.498 23.493 23.472 0.021
3 1 1 24.346 24.341 24.343 -0.002
1 0 4 24.569 24.565 24.570 -0.006
2 3 1 25.185 25.181 25.184 -0.003
1 3 3 27.155 27.151 27.144 0.006
2 1 4 28.680 28.676 28.667 0.008
1 4 2 29.272 29.268 29.268 0.000
3 1 3 29.518 29.514 29.526 -0.012
2 3 3 30.235 30.230 30.233 -0.003
M(20) = 19.32
F(20) = 49.24 ( 0.0083, 49)