Optimized Molecular Geometries, Internal Coordinates, Vibrational Analysis, Thermodynamic Properties, First Hyperpolarizability and HOMO-LUMO Analysis of Duroquinone Using Density Functional Theory and Hartree-Fock Method

The FTIR and FT-Raman spectra of Duroquinone have been recorded in the regions 4000-400 and 3500-50 cm(-1) respectively. Using the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compound has been carried out. The optimum molecular geometry, harmonic vibrational frequencies, infrared intensities and Raman scattering activities, were calculated by the density functional theory (DFT/B3LYP) method with 6-311++G(d, p) basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of Duroquinone is also reported. The thermodynamic parameters and first hyperpolarizability are calculated using DFT method. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule.