CRYSTAL STRUCTURE AND SPECTROSCOPIC STUDIES OF A NICKEL(II) COMPLEX OF A LIGAND CONTAINING NITROGEN-SULPHUR DONORS

Abstract

A bis-ligand neutral Ni(II) complex of a Schiff base ligand derived from S-benzyldithiocarbazate and p-dimethylaminobenzyldehyde was prepared and characterized. Single crystal X-ray diffraction analysis of the nickel(II) chelate established that the Schiff base loses a proton from its tautomeric thiol form and coordinates to Ni(II) via the mercapto sulphur and β-nitrogen atoms. The geometry of the Ni(II) ion is square-planar with two equivalent Ni-N and Ni-S bonds; the two dimethylaminobenzyl rings and the coordinated plane are almost in one plane, forming an electronic delocalization system. When the complex crystallizes, benzene molecules are included in the crystal. However, there is no obvious interaction between the complex molecule and the benzene molecule. Magnetic and spectroscopic data support the square-planar structure found in the structure analysis.

The complex crystallizes in the triclinic space group P1 with cell parameters a = 7.839(2), b = 10.528(4), c = 10.832(5) Å, α = 100.61(2), β = 92.39(2), γ = 93.99(2)° and Z = 1. The structure was refined by full-matrix least-squares to R = 0.050 and R_w = 0.064, with 2955 reflections having I>3[sgrave](I).

Key Words:

• Nikel(II)
• crystal structures
• Schiff base