Conformational, Optoelectronic and Vibrational Properties of the Entacapone Molecule: A Quantum Chemistry Study.

ABSTRACT

A quantum chemistry study were carried out looking for the conformational, optoelectronic and vibrational properties of the entacapone molecule, an efficient drug used in the Parkinson's disease treatment. Classical annealing was performed to explore the entacapone's molecular configurations, searching for optimal geometries. The quantum optimization calculations were made using three different functional combination levels of the density functional theory (DFT). The structural data (bond length, bond and torsion angles), charge population analysis (absorption spectra) and molecular orbital study (HOMO and LUMO) were obtained considering the lower energy optimized conformation of the entacapone molecule. Furthermore, a complete assignment of the harmonic vibrational frequencies were achieved through their infrared (IR) and Raman spectra.