Synthesis, spectral, crystal structures, Hirshfeld surface analysis and DFT studies on phenylmercury(II) dithiocarbamate complexes and their utility for the preparation of mercury sulfide nanoparticles

Abstract

Three new phenylmercury(II) dithiocarbamate complexes incorporating the furyl moiety, namely (N,N-difurfuryldithiocarbamato-S,S′)phenylmercury(II) (1), (N-furfuryl-N-(4-chlorobenzyl)dithiocarbamato-S,S′)phenylmercury(II) (2), and (N-furfuryl-N-(2-phenylethyl)dithiocarbamato-S,S′)phenylmercury(II) (3) have been prepared and characterized by elemental analysis, IR, 1H, and 13C NMR spectroscopy and X-ray crystallography. The crystal structures of 1, 2 and 3 show a linear mercury(II) core at the centre of the molecules. Weak intermolecular Hg⋯S interactions in 2 and 3 lead to the formation of linear chain and head to tail dimers, respectively. The Hirshfeld surface analysis and the associated 2D fingerprint plots of 1–3 have been also studied to evaluate intermolecular interactions. Theoretical calculations of isolated molecules of 1–3 have been performed using DFT method at B3LYP-LANL2DZ basis set. The geometrical parameters of 1–3 are in a good agreement with those obtained from the XRD experiment. The energy gap between EHOMO and ELUMO have been calculated. The molecular electrostatic potential (MEP) analysis support the substantial contribution of the resonance structure R1R2N+ = CS22− to the description of their structures. Complex 1 has been utilized as single source precursor to afford mercury sulfide nanoparticles via solvothermal decomposition in ethylenediammine. The as-prepared HgS nanoparticles were characterized using powder X-ray diffraction (PXRD), Transmission electron microscopy (TEM), Energy dispersive X-ray spectra (EDS) and Diffuse reflectance spectra(DRS). The band gap energy calculated from DRS spectrum shows evidence of quantum confinement.