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Bis(1-chloro-2,2,4,4-tetramethyl-3-oxocyclobutan-1-yl)pentasulfane: an occupancy modulated structure
A David Rae1, Anthony Linden, Agnieszka Majchrzak
1Research School of Chemistry, The Australian National University, Canberra 0200.
Abstract:
The title compound crystallizes in the space group P2(1)/n and may be described by a partial ordering of a 1:1 disordered P2(1)/a parent structure with the c axis halved. The pentasulfane chain completes a full turn of a helix, which gives molecules containing left- or right-handed helices similar spatial requirements and allows them to be interchanged. The structure can be redescribed as containing 0.732 (1) of an ordered P2(1)/n structure and 0.268 (1) of a 1:1 disordered P2(1)/a structure, implying that 0.134 (1) of the molecule sites contain molecules of the opposite hand to that predicted by an ordered P2(1)/n structure. It is found that the average molecular position in the asymmetric unit is not the same for each component and that these structural differences must be recognized to obtain a satisfactory refinement.
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