title: Vibrational, UV spectra, NBO, first order hyperpolarizability and HOMO-LUMO analysis of carvedilol.
abstract: In this work, we have investigated experimentally and theoretically on the molecular structure, vibrational spectra, UV spectral analysis and NBO studies of cardio-protective drug carvedilol. The FT-Raman and FT-IR spectra for carvedilol in the solid phase have been recorded in the region 4000-100 cm(-1) and 4000-400 cm(-1) respectively. Theoretical calculations were performed by using density functional theory (DFT) method at B3LYP/6-31G(d,p) and B3LYP/6-31++G(d,p) basis set levels. The harmonic vibrational frequencies, the optimized geometric parameters have been interpreted and compared with the reported experimental values. The complete vibrational assignments were performed on the basis of potential energy distribution (PED) of the vibrational modes. The thermodynamic properties and molecular electrostatic potential surfaces of the molecule were constructed. The electronic absorption spectrum was recorded in the region 400-200 nm and electronic properties such as HOMO and LUMO energies were calculated. The stability of the molecule arising from hyper conjugative interactions and charge delocalization have been analyzed from natural bond orbital (NBO) analysis. The first order hyperpolarizability of the title molecule was also calculated. The photo stability of carvedilol under different storage conditions were analyzed using UV-Vis spectral technique.
authors.affiliation: Department of Physics, SCSVMV University, Enathur, Kanchipuram 631561, TN, India. Electronic address: hiswarna@gmail.com.
authors.forename: N
authors.initials: N
authors.lastname: Swarnalatha
authors.affiliation: Research and Development, St. Peter's Institute of Higher Education and Research, St. Peter's University, Avadi, Chennai 600054, TN, India.
authors.forename: S
authors.initials: S
authors.lastname: Gunasekaran
authors.affiliation: Department of Physics, Arulmigu Palani Andavar College of Arts and Culture, Palani 624601, TN, India.
authors.forename: M
authors.initials: M
authors.lastname: Nagarajan
authors.affiliation: PG and Research Department of Physics, Presidency College, Chennai 600005, TN, India.
authors.forename: S
authors.initials: S
authors.lastname: Srinivasan
authors.affiliation: Department of Physics, Meenakshi College for Women, Chennai 600024, TN, India.
authors.forename: G
authors.initials: G
authors.lastname: Sankari
authors.affiliation: Department of Physics, C. Kandaswami Naidu College for Men in Anna Nagar East, Chennai 600102, TN, India.
authors.forename: G R
authors.initials: GR
authors.lastname: Ramkumaar
mesh_terms: D000959:Antihypertensive Agents / Q000737:chemistry*; D002227:Carbazoles / Q000737:chemistry*; D000077261:Carvedilol; D008958:Models, Molecular; D011412:Propanolamines / Q000737:chemistry*; D011789:Quantum Theory; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D000959:Antihypertensive Agents; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol
keywords: Carvedilol; DFT; FT-IR; NBO; Topological charge