Competing Deactivation Channels for Excited π-Stacked Cytosines

Joint Authors

Dou, Yusheng
Yuan, Shuai
Hong, Huiling
Wang, Gang
Zhang, Wenying
Lo, Glenn V.

Source

International Journal of Photoenergy

Issue

Vol. 2014, Issue 2014 (31 Dec. 2014), pp.1-9, 9 p.

Publisher

Hindawi Publishing Corporation

Publication Date

2014-08-03

Country of Publication

Egypt

No. of Pages

9

Main Subjects

Chemistry

Abstract EN

The deactivation of π-stacked cytosine molecules following excitation by ultrashort laser pulses was studied using semiclassical dynamics simulations.

Another deactivation channel was found to compete with a previously reported path that led to dimerization.

For both pathways, the initial excited state was found to form a charge-separated neutral exciton state, which forms an excimer state by charge transfer.

When the interbase distance becomes less than 3 Å, charge recombination occurs due to strong intermolecular interaction, ultimately leading to an avoided crossing.

Results indicate that the C2–N1–C6–C5 and C 2 ′ – N 1 ′ – C 6 ′ – C 5 ′ dihedral angles play a significant role in the vibronic coupling between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO).

Vibrational energy distribution determines the fate of the excimer at the avoided crossing.

Higher-amplitude vibration of C5 or C6 atoms leads to a nonadiabatic transition to the electronic ground state (a photophysical pathway); otherwise, a chemical reaction leading to the formation of cyclobutane type dimer occurs as found in earlier studies.

The S1 and S0 potential energy surfaces calculated at TD-DFT level and the simulated trajectories were found to be consistent with CASPT2 results.

American Psychological Association (APA)

Yuan, Shuai& Hong, Huiling& Wang, Gang& Zhang, Wenying& Dou, Yusheng& Lo, Glenn V.. 2014. Competing Deactivation Channels for Excited π-Stacked Cytosines. International Journal of Photoenergy،Vol. 2014, no. 2014, pp.1-9.
https://search.emarefa.net/detail/BIM-1036787

Modern Language Association (MLA)

Yuan, Shuai…[et al.]. Competing Deactivation Channels for Excited π-Stacked Cytosines. International Journal of Photoenergy No. 2014 (2014), pp.1-9.
https://search.emarefa.net/detail/BIM-1036787

American Medical Association (AMA)

Yuan, Shuai& Hong, Huiling& Wang, Gang& Zhang, Wenying& Dou, Yusheng& Lo, Glenn V.. Competing Deactivation Channels for Excited π-Stacked Cytosines. International Journal of Photoenergy. 2014. Vol. 2014, no. 2014, pp.1-9.
https://search.emarefa.net/detail/BIM-1036787

Data Type

Journal Articles

Language

English

Notes

Includes bibliographical references

Record ID

BIM-1036787