The crystal structures of bis(3,5-diphenyl-1,2-dithiolium) tetrachloroferrate(II) and of bis-(3,5-diphenyl-1,2-dithiolium) tetrachloromercurate(II)

Abstract

The crystal structure analyses are based on three-dimensional diffractometer data with least-squares refinement of the scattering model. Crystals are triclinic, space group Ci, with two formula units per asymmetric unit (Z=4). Cell dimensions, with values for the tetrachloromercurate isomer given in parentheses, are a= 16.22 (16-26), b=22.28 (22.31), e= 16.95 (17.12) A, e=94"9 (94-5), fl=82-7 (82-8) and y= 100.4 (99.6) °. Terminal R values for the two analyses are 0.047 (4621 reflexions) and 0.044 (4079 reflexions) respectively. In both complexes, similarly located tetrachlorometallate ions show marked, but very similar, angular distortions from tetrahedral symmetry. Both the angular distortions and M-C1 bond-length inequivalences are related to local Cl-..S(dithiolium) charge transfer interactions. Some comments are made regarding the possible relevance of such anion-cation interactions to non-valence interactions and mechanisms of electron transfer in metalloenzymes.