Theoretical study of the solvent effects on electronic properties of 2(1H)-quinoxalinone derivatives

Abstract

The structures and electronic spectra of three quinoxalinone derivatives have been investigated theoretically by performing DFT and TDDFT calculations with standard basis sets containing polarization and diffuse functions. The solvent effect was taken into account using self-consistent isodensity polarized continuum model (SCIPCM); three polar solvents were considered. The effect of the solvent polarity on the geometries, solvation energies, dipole moment, energy gap between HOMO and LUMO and UV-visible electronic transitions were examined for all studied compounds. The theoretical electronic spectrum of 2(1H)-quinoxalinone was compared with the experimental one. The experimental electronic spectrum recorded in ethanol exhibit three absorption bands respectively at 230, 280 and 220 nm. The existence of these bands has been confirmed by TDDFT calculations for the studied quinoxalinone derivatives. The effects of solvent polarity and the nature of the substituent of the quinoxalinone on the displacement of the calculated absorption bands are discussed.