FRONTIER MOLECULAR, NATURAL BOND ORBITAL, UV-VIS SPECTRAL STUDY, SOLVENT INFLUENCE ON GEOMETRIC PARAMETERS, VIBRATIONAL FREQUENCIES AND SOLVATION ENERGIES OF 8-HYDROXYQUINOLINEAbstract
N-heterocyclic compounds have extensive biological and pharmaceutical applications. 8-Hydroxyquinoline (8-HQ) also plays a significant role in many fields of life. The excellent biological significance of the 8-HQ prompted us to extend the DFT based studies. The frontier molecular orbitals (FMOs), UV-VIS and solvation model based studies remained unknown. Therefore, we intended to study the natural bond orbital, FMOs, UV-VIS, thermodynamic properties and medium influence on solvation energies, dipole moment, FT-IR and FT-Raman using polarizable continuum model (PCM) and density-based solvation model (SMD). The electronic properties of molecule were calculated by M06-2X/6-31G (d,P) and B3LYP/6-31G (d,p) level of theories. The solvent influence on the geometric parameters, FT-IR and FT-Raman were studied by B3LYP /6-31G(d) method. A good correspondence is found between the optimized parameters and the reported X-ray data. Natural bond orbital reveals that the maximum stabilization energy reached up to 39.64kJ/mol which is responsible for extra stability of the molecule. In solvated 8-HQ, a significant medium effects on FT-IR and FT-Raman intensities is observed. The intensities enhanced from gas to solvent phase. The solvation free energies are found to be -28.710 and -39.456 kJ/mol in PCM and SMD models respectively. FMOs suggested that this molecule contain less hardness and larger softness values. These findings reveal that the molecule might be bioactive.
Md. Khalid *, Md. Ali, Md. Aslam, S. H. Sumrra, Md. U. Khan, N. Raza, N. Kumar and Md. Imran
Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes, São Paulo, Brazil.
06 August, 2016
26 October, 2016
17 November, 2016
01 February, 2017