NATURAL SCIENCES

Journal of fundamental
and
applied researches

Structural dynamic model and spectroscopicidentification ethyluracil in the condensed state

2013. №4, pp. 183-190

Elkin Mihail D. - D.Sc. (Physics and Mathematics), Professor, Astrakhan State University, 20a Tatishchev Str., Astrakhan, 414056, Russian Federation, elkinmd@mail.ru

Smirnov Vladimir V. - D.Sc. (Pedagogy), Associate Professor, Astrakhan State University, 20a Tatishchev Str., Astrakhan, 414056, Russian Federation, kof@aspu.ru

Dzhalmuhambetova Elena A. - Ph.D. (Physics and Mathematics), Associate Professor, Astrakhan State University, 20a Tatishchev Str., Astrakhan, 414056, Russian Federation, kof@aspu.ru

Grechukhina Oksana N. - Ph.D. (Physics and Mathematics), Associate Professor, Astrakhan State University, 20a Tatishchev Str., Astrakhan, 414056, Russian Federation, kof@aspu.ru

Alykova Olga M. - Ph.D. (Pedagogy), Associate Professor, Astrakhan State University, 20a Tatishchev Str., Astrakhan, 414056, Russian Federation, kof@aspu.ru

In the work within the framework of the method the density functional DFT/B3LYP are constructed structural dynamic model of uracil DNA bases. These results of the evaluation geometry of methyl-substituted uracil indicate that the change of parameters depending on the location of the methyl portion does not exceed ~0.01 ? for the valence bonds and ~4? for bond angles and lies within the boundaries of the influence of bases of calculation. The formation of dimers leads to a change in the corresponding geometric parameters within the framework specified limits. For the spectral identification of uracil dimers and substituted can be used intense bands interpreted as the valence vibrations of NH (qNH), involved in the formation of hydrogen bonds. The frequency of oscillation of the solid plane not links (?NH) move in the shortwave range on the value of the same order (INFRARED spectrum area). The reliability of the results is confirmed by their coincidence with experimental data on the vibrational spectra for the methyl-substituted uracil.

Key words: methyl-substituted uracil,uracil,dimer,conformer,tautomer,density functiona,vibrational spectra,anharmonic,adiabatic potential