Second example of non-merohedral twinning

The data for the structure of 2-(chloro-methyl)p3Tidinium chloride (Jones et al., 2002) was collected on a Bruker SMART 1000 CCD area detector. The normal indexing program failed and split reflections profiles combined with nice profiles and reflections very close to each other indicated that this was a non-merohedral twin. The program CELL NOW easily finds two orientation matrices (see nonm2 cn)  

Percentages of reflections in this domain not consistent with lattice types  

465 reflections within 0.200 of an integer index assigned to domain 1, 465 of them exclusively 96 reflections not yet assigned to a domain 

Rotated from first domain by 179.5 degrees about 

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