A computer simulation study of local arrangements in disordered molecular crystals

Local molecular arrangements have been generated with the help of Monte Carlo computer simulation using experimentally measured short-range-order parameters in two isostructural (monoclinic) isomers of dibromodimethyldiethylbenzene. The computer program was based on the GC concept of Gehlen & Cohen [Phys. Rev. A (1965), 139, 844-855] modified for use with molecular crystals. It is seen that the atomic contact distances play an important role and the first nine short-range-order parameters were required to obtain a reliable picture of the structure of the disordered molecular crystal. Microstructures for the two isomers were found to be very similar.