Dear,
Sorry for the off-topic question.
I'm facing a (probably) merohedral twinning problem, regarding a small
molecule.
Using Xprep, I get a Hexagonal P-lattice with cell:
18.014 18.014 22.048 90.00 90.00 120.00
Mean |E*E-1| = 0.902 [expected .968 centrosym and .736 non-centrosym]
However, based on the systematic absence exceptions, the probable
(apparent) SG's are:
P6(3)/m (Laue '6/m')
P6(3) (Laue '6')
P6(3)22 (Laue '622')
61/65 62=31 63 -c- --c
N 60 50 36 2471 1420
N I>3s 19 19 0 420 161
<I> 186.6 223.1 4.6 30.0 15.5
<I/s> 2.3 2.6 0.3 1.6 1.2
I know there is a twin law to transform the (apparent) Laue group '6/
m' to the (true) Laue group '-3'
(TWIN law -1 0 0 0 -1 0 0 0 1) and merging the data in a trigonal SG,
but this is not solving the structure at all...
Has anyone noticed a similar case that could be of any help please..?
Many thanks
Kristof
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