A computational study on the second-order nonlinear optical response of a new unsymmetrical oxovanadium complex

Abstract

A new unsymmetrical N2O2 Schiff base oxovanadium (IV) complex, VOLPy, was synthesized with excellent yield and characterized using conventional methods. The crystal structure of the VOLPy complex was determined through X-ray diffraction, revealing a distorted square pyramidal coordination configuration around the central vanadium ion. The solid-state structure is stabilized by various non-covalent short contacts, generating complex 3D supramolecular network. The electrochemical properties of the VOLPy complex were investigated in different media, demonstrating diffusion-controlled reversible or quasi-reversible processes within the potential range of 200–1000 mV, involving a single electron VV/VIV reduction. The diffusion coefficients were calculated using Levich plots Ilim = f(ω1/2). Using quantum calculations at the CAM-B3LYP level with a 6-311G**/LanL2DZ basis set, we systematically assessed various structural parameters, electronic properties, linear and nonlinear optical responses at static and dynamic regimes for oxovanadium complexes, V(V)OL and V(IV)OL, in both gaseous and solvent environments. The results reveal a robust alignment between quantum calculations and experimental data, with only minor deviations. This study anticipates that these specifically designated complexes hold substantial potential as excellent candidates for second-order nonlinear optical (NLO) materials.