title: Structural study, NCA, FT-IR, FT-Raman spectral investigations, NBO analysis, thermodynamic functions of N-acetyl-l-phenylalanine.
abstract: The FT-IR and FT-Raman spectra of N-acetyl-l-phenylalanine were recorded and analyzed. Natural bond orbital analysis has been carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. HOMO-LUMO energy gap has been computed with the help of density functional theory. The statistical thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) were obtained for the range of temperature 100-1000K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the experimental and theoretical spectra values provides important information about the ability of the computational method to describe the vibrational modes.
authors.affiliation: Department of Physics, Government Arts College, Kulithalai 639120, Karur, India.
authors.forename: B
authors.initials: B
authors.lastname: Raja
authors.affiliation: Research Department of Physics, A.A. Government Arts College, Musiri 621211, India. Electronic address: brsbala@rediffmail.com.
authors.forename: V
authors.initials: V
authors.lastname: Balachandran
authors.affiliation: Research Department of Physics, A.A. Government Arts College, Musiri 621211, India.
authors.forename: B
authors.initials: B
authors.lastname: Revathi
mesh_terms: D000465:Algorithms; D002244:Carbon / Q000737:chemistry; D003198:Computer Simulation; D006859:Hydrogen / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D016011:Normal Distribution; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000737:chemistry; D012984:Software; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity; D013696:Temperature; D013816:Thermodynamics; D014732:Vibration
chemical_list: C476995:3-(4-acetylphenyl)-2-aminopropanoic acid; D010649:Phenylalanine; D002244:Carbon; D006859:Hydrogen
keywords: HOMO–LUMO; MEP surface; N-acetyl-l-phenylalanine; NBO; Vibrational spectra