title: Vibrational spectra, tautomerism and thermodynamics of anticarcinogenic drug: 5-fluorouracil.
abstract: The FT-IR and FT-Raman spectra of 5-Fluorouracil were recorded in the solid phase in the regions 400-4000 cm(-1) and 50-4000 cm(-1), respectively. The vibrational spectra were analysed and the observed fundamentals were assigned to different normal modes of vibration. The experimental wavenumbers were compared with the scaled vibrational values using DFT methods: the Ar matrix data were related to gas phase calculations, while the values of the solid state spectra were compared to those with dimer simulations. The study indicates that some features that are characteristic of vibrational spectra of uracil and its derivatives are retained in the spectrum of 5-fluorouracil and it exists in ketonic form in the solid phase. The tautomerism was also studied and the spectra of the two most stable forms were simulated. The calculated wavenumbers have been employed to yield thermodynamic properties.
authors.affiliation: Department of Physics, CCS University, Meerut 250 004, India. asian_c_l@rediffmail.com
authors.forename: V K
authors.initials: VK
authors.lastname: Rastogi
authors.forename: M Alcolea
authors.initials: MA
authors.lastname: Palafox
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000737:chemistry*; D005472:Fluorouracil / Q000737:chemistry*; D008956:Models, Chemical; D008968:Molecular Conformation; D015394:Molecular Structure; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014732:Vibration
chemical_list: D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil