Spectral and structural studies on Ni(II) dithiocarbamates: Nickel sulfide nanoparticles from a dithiocarbamate precursor

Three new planar Ni(II) dithiocarbamate complexes; [Ni(4-dpmpzdtc)₂] (1), [Ni(4-dpmpzdtc)(PPh₃)(NCS)] (2) and [Ni(bupcbzdtc)(PPh₃)(NCS)] (3) (where, 4-dpmpzdtc = 4-(diphenylmethyl)piperazinecarbodithioato anion, bupcbzdtc = N-butyl-N-(4-chlorobenzyl))dithiocarbamato anion and PPh₃ = triphenylphosphine) with "NiS₄" and "NiS₂PN" chromophore units were synthesized and characterized by single crystal X-ray structural analysis as well as UV-Vis, IR and NMR (¹H, ¹³C and ³¹P) spectroscopy. For 2, ¹H-¹H COSY spectrum was also recorded. Single crystal X-ray structural analysis of 1-3, reveals a slightly distorted square planar geometry in all three complexes wherein the steric and electronic influence of auxiliary ligands PPh₃ and NCS^- induces change in the bonding parameters of the latter two complexes (especially in 3). Nickel sulfide nanoparticles were produced from complex 1 by solvothermal synthesis. The morphology and a qualitative phase analysis of the nanoparticles are also viewed in the study.