XPS, single crystal X-ray diffraction and cyclic voltammetric studies on 1,10-phenanthroline and 2,2 '-bipyridine adducts of bis(piperidinecarbodithioato-S,S ')cadmium(II) with CdS(4)N(2) environment - A stereochemical and electronic distribution investigation

(1,10-Phenanthroline)bis(piperidinecarbodithioato-S,S')cadmium(II), [Cd(pipdtc)(2)(1,10-phen)] (1) and (2,2'-bipyridine)bis(piperidinecarbodithioato-S,S')cadmium(II), [Cd(pipdtc)(2)(bipy)] (2) adducts were prepared and the crystal structures are reported. Cd-S and Cd-N distances and the angles subtended at cadmium are almost the same in both complexes but the Cd-S distances in the adducts are longer than those in Cd(pipdtc)2 (3) complexes due to the presence of an additional neutral ligand. Thioureide C-N distance in 1 and 2 are supported by vC-N bands observed at 1471 and 1470 cm(-1), respectively. S2p binding energies for the adducts show a significant reduction in value compared to the parent dithiocarbamate indicating the weakening of the Cd-S bond on adduct formation. The observed reduction in binding energy is due to the increased electron density on the metal in the adducts. The cyclic voltammetric study on the complexes also show an increase of electron density on cadmium in the adducts compared to Cd(pipdtc)(2). (c) 2008 Elsevier Ltd. All rights reserved.