Structural studies of steric effects in phosphine complexes: Dimers of bis-{dithiocyanato(1-phenyl-dibenzophosphole)mercury(II)} associate with significant Hg-N and Hg-S interdimer interactions

The title compound, [Hg(SCN)(2)(C6H5)P(C12H8)](2), exists as a dimer with t wo-fold crystallographic symmetry in the solid state with the Hg atoms link ed by bridging N- and S-thiocyanato atoms. There are four primary bonds to each Hg atom, Hg-N, 2.771(4) Angstrom, Hg-P, 2.4084(11) Angstrom and two Hg -S, 2.4565(10) Angstrom and 2.6055(13) Angstrom, resulting in a distorted t rigonal pyramidal geometry about the metal centre. The dimers associate abo ut inversion centres to form infinite one-dimensional chains by weaker Hg . .. N 3.178(5) Angstrom and Hg ... S 3.6027(14) Angstrom interactions, givin g an overall distorted octahedral coordination geometry for each Hg atom. T he Hg-P bond lies approximately orthogonal to the .. Hg .. Hg .. chain and the benzophosphole group forms a 'sandwich' preventing interactions between the Hg(SCN)(2) moieties in neighbouring chains.