No abstract

No abstract

No abstract

No abstract

The c/s and trans isomers of 1,2-bis(4-chlorophenyl)-1,2-dichloroethylene, C14HsC14, are monoclinic, space group P21/c. The 107 parameters describing the trans isomer [a = 6.002 (5), b = 14.500 (12), c = 7.630 (5) A,/~ = 94.55 (2) °, Z = 2, Dx = 1. 596 g cm-31 were refined versus the 854 most significant single-crystal Xray reflexions to an R of 0.043. The 195 parameters of the cis isomer [a = 8.062 (8), b = 28.560 (12), c = 6.118 (6) A,/3 = 97.60 (2) °, Z = 4, Dx = 1.513 g cm-31 were refined versus the 1017 most significant reflexions to an R of 0.048. The molecules of both isomers were found to be nonplanar. The C-C=C bond angles at the ethylene bridge were significantly greater than 120 (125) for the cis isomer and less than 120 ° ( 118 o) for the trans isomer.