An old oxovanadium(IV) complex of N-(salicylidene)sulfanilamide: theoretical validity of experimental observations

Abstract

Sulfa drug Schiff base complexes of oxovanadium are counted among highly significant molecular scaffolds of industrial and medicinal relevance. In order to present a theoretical validation of our earlier reported complex of this sort herein, a comparative experimental theoretical investigation of N-(salicylidene)sulfanilamide Schiff base and its oxovanadium(IV) complex, [VO(sal-snm)2(H2O)] based on density functional theory calculations using the B3LYP as functional and 6-31++G(d,p) (for ligand)/LANL2DZ (for Vanadium) basis set is being reported. The calculated vibrational frequencies have been compared with experimental FT-IR spectra of the selected compounds. The Molecular geometry optimizations, frontier orbital analysis, hyperpolarizability calculations and molecular electrostatic surface potential (MESP) topologies of the title compounds have been sought in this work. From the molecular geometrical optimization of the oxovanadium(IV) complex a suitable octahedral structure has been confirmed. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecules. The Non-linear optical properties encompassing the applicability of electric dipole moment (μ), polarizability (α), mean polarizability (Δα) and hyperpolarizability (β0) values have been evaluated through quantum chemical calculations.