Abstract:
High-resolution spectra of single-chain short oligonucleotides d(20G, 20T), where d is a deoxyribonucleoside, G is guanine, and T is thymine, have been obtained by the highly sensitive nonresonant Raman scattering method of biomacromolecules. In addition to their own multifunctional significance, short oligonucleotides attract interest as ideal model objects for revealing poorly studied peculiarities of tertiary and quaternary structures of DNA. The detection of narrow spectral lines has allowed determining the characteristic time scale and makes it possible to study the dynamics of fast relaxation processes of vibrational motions of atoms in biomacromolecules. It has been found that the FWHM of the narrowest $1355.4$ cm$^{-1}$ spectral line attributed to the vibrations of the dT methyl group is $14.6$ cm$^{-1}$. The corresponding lifetime is $0.38$ ps.