Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5393606 | Computational and Theoretical Chemistry | 2014 | 7 Pages |
â¢Simulating the structure of DNA bases and a tautomerism of thymine.â¢Calculating the HHG spectra from DNA bases.â¢Four bases are distinguish into two groups: adenine, guanine and cytosine, thymine.â¢Keto-enol tautomerism in thymine may be probed by the HHG spectra.
We point out the possibility to distinguish the DNA bases (adenine, cytosine, guanine and thymine) by using the high-order harmonics sources. Moreover, we find the intensity peaks of the high-order harmonics emitted by thymine base while this molecule is near the stable states (keto and enol) as well as at the transition state along the chemical reaction path of a tautomerism. This finding shows the possibility of tracking the DNA tautomerism. Our investigation is based on the simulation method. The structures of four DNA bases and the keto-enol tautomerism of thymine are simulated by the molecular dynamics method within the Born-Oppenheimer approximation. High-order harmonics, emitted from the bases while molecules are exposed to ultrashort laser pulses are calculated by the strong-field approximation within the Lewenstein model. The calculated data then are used as 'experimental' high-order harmonics sources for investigation.
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