Studies on optical, electrical, mechanical and theoretical investigation of 4-nitro-benzoic acid (3-ethoxy-2-hydroxy-benzylidene)-hydrazide: A novel Schiff base organic NLO material

Abstract

New organic non-centrosymmetric Schiff base material 4-Nitro-benzoic acid (3-ethoxy-2-hydroxy-benzylidene)-hydrazide was synthesized and grown as single crystal by slow evaporation solution growth technique. Single crystal X-ray diffraction reveals the noncentrosymmetric nature of the grown crystal with space group Pna21. The nonlinear efficiency of the grown material was studied by Kurtz-Perry powder technique and found to be 0.7 times that of KDP. The photoluminescence emission of the grown crystal shows emission at 360 nm. The mechanical stability of the crystal was examined by Vicker's microhardness study and the yield strength of the material was calculated. Low dielectric constant at higher frequencies was observed from dielectric measurements. Reduction in charge carriers when the sample was illuminated by halogen lamp proves the negative photoconductivity of the sample. In addition, quantum chemical calculations were carried out using density functional theory for the NEH molecule optimized at B3LYP/6-31 + G (d, p) basis set to calculate its frontier molecular orbital, electrostatic potential and Mulliken charge analysis.