On the internal photorelaxation mechanism of DNA
| dc.creator | Czader, Arkadiusz | |
| dc.creator | Bittner, Eric R. | |
| dc.date | 2008-11-04 | |
| dc.date.accessioned | 2026-07-07T10:15:38Z | |
| dc.date.available | 2026-07-07T10:15:38Z | |
| dc.description | We propose a model for the photo-deactivation mechanism for DNA based upon accurate quantum chemical and molecular dynamical evaluations of model Watson/Crick nucleoside pairs and stacked pairs. Our results corroborate recent ultrafast experimental studies on DNA oligonucleotides and suggest that following photo-excitation to a local $π-π^*$ state, the excitation is rapidly delocalized over several (3-4) bases on an ultrafast time-scale. However, this delocalized state is unstable with respect to the motions of the protons involved in hydrogen-bonding between Watson/Crick pairs and rapidly re-localizes to a charge-transfer state on a longer time-scale ranging from 10 to 100 ps. This state, too, is unstable and relaxes via a conical intersection with the ground state near the geometry of the enol- and imino-tautomeric form. We suggest that this internal deactivation mechanism is responsible for the intrinsic photostability of DNA. | |
| dc.description | 5 pages, 5 figures | |
| dc.identifier | https://arxiv.org/abs/0811.0625 | |
| dc.identifier | http://arxiv.org/abs/0811.0625 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/173233 | |
| dc.subject | Soft Condensed Matter | |
| dc.title | On the internal photorelaxation mechanism of DNA | |
| dc.type | text |