Structural variations in zinc(II) complexes with N,N-di(4-fluorobenzyl)dithiocarbamate and imines: New precursor for zinc sulfide nanoparticles

Abstract

Bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)zinc(II) (1), bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)(pyridine-κN)zinc(II) (2), (μ-4,4′-bipyridine-κ2N,N′)bis[bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)zinc(II)] (3) and (2,2′-bipyridine-κ2N,N′)bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κS,S′)zinc(II) (4) were prepared and characterized by elemental analysis, spectroscopy (IR, 1H and 13C NMR) and their structures were elucidated by X-ray crystallography. The centrosymmetric dinuclear structure of 1 features both bridging and chelating dithiocarbamate ligands to that a distorted trigonal bipyramidal S5 coordination geometry results. The coordination geometry of zinc(II) in 2 and both zinc(II) in the dinuclear complex 3 is an intermediate between tetragonal pyramidal and trigonal bipyramidal. In complex 4, the resulting N2S4 donor set defines a distorted octahedral geometry. Addition of imines (pyridine, 4,4′-bipyridine and 2,2′-bipyridine) to the complex 1 affects the ZnS distances and SZnS angles. The optimized geometry, HOMO-LUMO in the ground state and MEP have been calculated for 1 and 2. MEP analysis support the substantial contribution of the resonance structure RR′-N+CS22− to the description of their structures on the complexes 1 and 2. Quantification of the intermolecular interactions present in 1–4 was realized by Hirshfeld surface analysis. Zinc sulfide nanoparticles were prepared from 1 and characterized by PXRD, SEM, TEM, EDAX and DRS. The PXRD study showed that the nanoparticles is composed of cubic phase of zinc sulfide. Photocatalytic activity of as-prepared ZnS was tested by examining the degradation of rhodamine-B in aqueous solution under UV light illumination.