title: Molecular structure and vibrational spectra of Irinotecan: a density functional theoretical study.
abstract: The solid phase FTIR and FT-Raman spectra of Irinotecan have been recorded in the regions 400-4000 and 50-4000 cm(-1), respectively. The spectra were interpreted in terms of fundamentals modes, combination and overtone bands. The structure of the molecule was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-31G(d) as basis set. The vibrational frequencies were calculated for Irinotecan by DFT method and were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. The infrared spectrum was also simulated from the calculated intensities. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations.
authors.affiliation: Department of Physics (Engg.), Annamalai University, Annamalai Nagar, Chidambaram 608 002, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Chinna Babu
authors.forename: N
authors.initials: N
authors.lastname: Sundaraganesan
authors.forename: S
authors.initials: S
authors.lastname: Sudha
authors.forename: V
authors.initials: V
authors.lastname: Aroulmoji
authors.forename: E
authors.initials: E
authors.lastname: Murano
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry*; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000737:chemistry; D000077146:Irinotecan; D008958:Models, Molecular; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity; D059004:Topoisomerase I Inhibitors / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D059004:Topoisomerase I Inhibitors; D000077146:Irinotecan; D002166:Camptothecin