Structural and vibrational spectral investigation on the identification of Non-Linear Optical properties and wave function analyses (electrostatic potential, electron localisation function, localised orbital locator) of 3-Ethoxy Salicilaldehyde

Abstract

ABSTRACT In the present study, 3-Ethoxy Salicilaldehyde (3ES) was investigated in terms of structural, vibrational spectroscopic and theoretical analyses. All the theoretical calculations were done with the density functional theory method. The natural bond orbital analysis had been done to understand the probable charge transfer interaction in the molecule. The Frontier molecular orbitlas’ molecular electrostatic potential surface has been plotted and the reactive sites of electrophilic and nucleophilic attacks of the molecule have been estimated. The possible vibrations were identified and analysed using the Vibrational Energy Distribution Analysis 4 (VEDA 4) program and Vibrational spectrum. The Fukui function analysis was also used to predict the reactive sites of electrophilic and nucleophilic attacks for the 3ES molecule. Based on electron density, weak interactions of the studied molecules were identified with the aid of RDG analysis. The dipole moment, polarisaility, first-order hyperpolarisability (α 0) and related properties (β, α 0 and Δα) and second-order hyperpolarisabilties were calculated for the identification of non-linear optical activity of the molecule. The second harmonic generation study also has been done for understanding the non-linear optical activity of the molecule.