The crystal structure of the 1:1 complex of s-trinitrobenzene and s-triaminobenzene

Abstract

The crystals of the 1 : 1 complex formed between s-trinitrobenzene and s-triaminobenzene are purpleblack needles and monoclinic, space group P2 ~/a with cell dimensions: a = 14.063, b = 15.079, c = 6982/~ fl= 103.5 ° and Z = 4 . The structure has been determined by a three-dimensional X-ray analysis using visually estimated Cu K~ data. Phases were found for 110 reflexions by the symbolic addition procedure and the subsequent refinement was carried out by block-diagonal least-squares with anisotropic temperature factors, to an R value of 0.082. The component molecules are stacked alternalely in infinite columns parallel to the c axis. The mean molecular planes are inclined at 69-3 : to the stacking axis. The average spacings between overlapping molecules are 3.24 and 3.29 A, respectively. Bond lengths and angles in the s-trinitrobenzene molecule are in reasonable agreement with the corresponding values for the same molecule in other s-trinitrobenzene complexes. For the s-triaminobenzene molecule the average values are found to be: C -C= 1.400, C N = 1.398 A, /_CCC= 1200 ~ and ACCN = 119-8 °. Nitrogen atoms of amino groups are slightly out of the plane of the benzene ring.