Molecular structure, spectroscopic, chemical reactivity, and nonlinear optical analysis of l-phenylalanine-benzoic acid optical crystals

By using density functional method, the molecular geometry, harmonic vibrational frequencies and bonding features of l-phenylalanine-benzoic acid in the ground state have been calculated. Stability of the molecule arising from hyper-conjugative interactions, charge delocalization has been analyzed using natural bond orbital analysis. The electron density based local reactivity descriptor such as Fukui functions was calculated to explain the chemical reactivity site in the molecule. The electronic properties, such as excitation energies, absorption wavelength, HOMO and LUMO energies were performed which confirm the charge transfer of the molecule. The theoretical results are valuable for providing a reliable insight into the vibrational spectra and molecular properties.