Synthesis, crystal structure, thermal and theoretical studies of bis(N-ethyl-N-phenyldithiocarbamato) Ni(II) and (N-ethyl-N-phenyldithiocarbamato) (isothiocyanato) (triphenylphosphine) Ni(II)

Abstract

Homoleptic and heteroleptic Ni(II) complexes represented as NiL 1 2 and NiL 1 L 2 L 3 (where, L 1 = N -ethyl-N -phenyldithiocarbamato anion, L 2 = isothiocyanato anion, and L 3 = triphenylphosphine) were synthesized. The complexes have been characterized by elemental, IR, NMR, and single-crystal X-ray analysis. The thermal decomposition behaviour of the complexes were studied using thermogravimetric analysis (TGA). The optimized geometry and the electronic analysis of the type of bonding within the complex structures were performed using methods based on the density functional theory and atom in molecule (AIM) analysis method. X-ray structural analysis of both complexes confirms distorted square planar geometry about the Ni atom. The TGA indicates that the complexes belong to the class of volatile dithiocarbamates which yield the corresponding metal sulphide without any intermediate products. Structural parameters from crystallographic and DFT studies have been compared and found to correlate with each other. The small discrepancies in geometric parameters are attributable to H-bonding and packing interactions within the lattice which are not modelled during computational study. AIM analysis suggests that in NiL 1 L 2 L 3 , the Ni· · · L interactions are more covalent in nature whereas in NiL 1 2 complex, they are more ionic in character.

Chemistry and Some Biological Potential of Bismuth and Antimony Dithiocarbamate Complexes

“…The shift in the stretching vibrational bands of υ(C-N) by 15 cm −1 upon complexation with a metal often suggests a partial double bond character. This band appears in a region between the single bond v(C-N) and the double bond v(C=N) stretching vibrations [14,57,58]. The appearance of a single or split band in the range 1000-950 cm −1 suggests a bidentate or a monodentate coordination mode respectively with the metal centre [59].…”