Molecular Packing in the Crystal Structures of the Mixed-Ligand Complexes [CdPhen{(i-C4H9)2PS2}2] and [Cd(2,2′-Bipy){(i-C4H9)2PS2}2]

Abstract

Single crystals of the mixed-ligand complex compounds of Cd(i-Bu₂PS₂)₂ with Phen and 2,2′-Bipy have been obtained. The crystal structures of the complexes [CdPhen{(i-C₄H₉)₂PS₂}₂] (I) and [Cd(2,2′-Bipy){(i-C₄H₉)₂PS₂}₂] (II) were determined by X-ray diffraction (CAD-4 diffractometer, MoK _α radiation, 1739 F _{F hkl} , R = 0.0417 for I and 2612 F _hkl , R = 0.0442 for II). Monoclinic crystals with unit cell parameters a = 15.640(3), b = 20.797(4), c = 11.559(2) Å, β = 111.21(3)°, V = 3505(1) ų, Z = 4, d _calc = 1.348 g/cm³, space group $P2_1 {\kern 1pt} /{\kern 1pt} c$ (I); a = 14.737(3), b = 20.918(4), c = 11.517(2) Å, β = 105.53(3)°, V = 3421(1) ų, Z = 4, d _calc = 1.334 g/cm³, space group $P2_1 {\kern 1pt} /{\kern 1pt} c$ (II). The structures consist of discrete monomer molecules. The coordination polyhedra of the Cd atoms are distorted octahedra formed by four S atoms of two cyclic bidentate ligands i-Bu₂ $PS_2^ -$ and two N atoms of the cyclic bidentate ligands — Phen or 2,$2'$-Bipy molecules. The interaction between molecules I and II in the structures and the packing modes are considered.