ANIONIC HALIDE AND ISOTHIOCYANATE ADDUCTS OF ZINC AND CADMIUM DITHIOCARBAMATES

The mixed-ligand complexes [NEt4][Zn(S2CNMe2)2X] (X = Cl, Br, or NCS) and [NR4][Cd(S2CNEt2)2X] (R = Et, X = Cl, Br, or NCS; R = Bu(n), X = l) have been prepared by reaction of zinc and cadmium bis(dithiocarbamate) with the tetraalkylammonium salt of the halide or thiocyanate in acetone at room temperature. The single-crystal X-ray structures of [NEt4][Zn(S2CNMe2)2(NCS)] 1 and [NEt4][Cd(S2CNEt2)2(NCS)] 2 were determined: 1, monoclinic, space group P2(1)/n, a = 9.447(l ), b = 16.661 (2), c = 15.807(1) angstrom, beta = 97.10(1)-degrees and Z = 4; 2, orthorhombic, space group P2(1)2(1)2(1), a = 16.213(1), b = 17.501 (2), c = 10.243(1) angstrom and Z = 4. The central Zn and Cd atoms show distorted trigonal-bipyramidal co-ordination geometry with the thiocyanate N atom occupying an equatorial position and the dithiocarbamate ligands spanning one axial and one equatorial position each. The infrared and Raman spectra (2100-50 cm-1) of the complexes are discussed. The metal-sulfur stretching frequencies are assigned in the ranges 226-205 (Zn-S) and 203-145 cm-1 (Cd-S), respectively.