Effect of hydrogen bonding on the structure and vibrational spectra of the complementary pairs of nucleic acid bases. II. adenine-thymine

The vibrational spectra of an isolated complementary adenine-thymine pair are calculated in the B3LYP/6-311++G(d,p) approximation and analyzed. The effect of hydrogen bonds on the structure is shown along with the position of frequencies and intensities of normal vibrations of the pair in comparison with the spectra of isolated thymine and adenine molecules. A comparative analysis of the hydrogen bonding effect on the IR and Raman spectra of thymine and adenine is performed