FTIR and FT-Raman spectra of 5-methyluracil (thymine)

Abstract

FTIR and FT‐Raman spectra of 5‐methyluracil (thymine) were recorded in the regions 400–4000 cm−1 and 50–4000 cm−1, respectively. The observed wavenumbers were analysed and assigned to different normal modes of vibration of the molecule. Ab initio and density functional calculations were performed to support the assignments of the observed wavenumbers. The geometry structure was determined and a comparison with the uracil molecule was made. Good reproducibility of the experimental wavenumbers was obtained at the B3LYP level and the percentage error was very small, less than 1% in most cases. Copyright © 2000 John Wiley & Sons, Ltd.

Monitoring the Presence of Ionic Mercury in Environmental Water by Plasmon-Enhanced Infrared Spectroscopy

“…In the case of s-polarization (Fig. 3(a)), C = O and C = C stretching peaks of thymine centered at ω = 1656 cm −1 and 1724 cm −1 (signal intensity of 0.2%) were observed18192021. In the case of p-polarization (Fig.…”

“…This process accompanies with the substantial charge re-distribution near the two N atoms in the imide structures (surrounded by red dotted square), and subsequently leads to the intensity change of the vibrational peak at ω T = 1400 cm −1 . Since this mode involves large displacement of the N atom in the imide structure181920, the observed antiabsorption peak at ω T = 1400 cm −1 is most possibly associated with the vibrational mode involving this N atom which sensitively reflects the dipole moment change owing to the formation of N-Hg II -N bonds. On the other hand, C = O related band at ω = 1724 cm −1 in the same imide structure shows only slight increase in the absorption intensity (indicated by small red arrows in Fig.…”

FTIR and FT‐Raman spectra and density functional computations of the vibrational spectra, molecular geometry and atomic charges of the biomolecule: 5‐bromouracil

“…They have been found to exert profound effects in a variety of microbiological and mammalian systems. 3 This compound is widely recognised today as an effective treatment modality, especially with tumours of the head, neck and breast. Extensive work, both theoretical and experimental, have been done on uracil and its derivatives.…”

Fabrication and Characterization of Hollow Microcapsules from Polyelectrolytes Bearing Thymine Pendant Groups for Ultraviolet‐B (UVB)‐Induced Crosslinking

“…In the presence of the (P 4+ /P 4− ) 3 coating, multiple additional Raman signals were observed. They are associated to the stretching modes of aromatic C=C (1618 cm −1 ), overlapped stretching modes of C−N and C=C groups of thymine (1587 cm −1 ), CH 2 deformations of the skeletal chain together with the thymine ring stretching (1383–1366 cm −1 ), C(6)‐H in‐plane bending in the thymine residue (1177 cm −1 ), and deformation of C(6)‐H and/or torsion of −CH 3 in thymine (915 cm −1 ) . After the CaCO 3 core removal with EDTA solution to produce the HMC suspension, the intense doublet band due to the CaCO 3 disappeared, and the Raman spectrum of the HCM was almost identical to that obtained with an equimolar solution of both polyelectrolytes (Figure F), confirming the successful elimination of the internal micromold.…”