Faccialà, Davide; Bonanomi, Matteo; Tenorio, Bruno Nunes Cabral; Avaldi, Lorenzo; Bolognesi, Paola; Callegari, Carlo; Coreno, Marcello; Coriani, Sonia; Decleva, Piero; Devetta, Michele; Došlić, Nađa; De Fanis, Alberto; Di Fraia, Michele; Lever, Fabiano; Mazza, Tommaso; Meyer, Michael; Mullins, Terry; Ovcharenko, Yevheniy; Pal, Nitish; Piancastelli, Maria Novella; Richter, Robert; Rivas, Daniel E.; Sapunar, Marin; Senfftleben, Björn; Usenko, Sergey; Vozzi, Caterina; Gühr, Markus; Prince, Kevin C.; Plekan, Oksana (2025) Unraveling the Relaxation Dynamics of Uracil: Insights from Time-Resolved X-ray Photoelectron Spectroscopy. Journal of the American Chemical Society, 147 (34). pp. 30694-30707. ISSN 0002-7863
![[img]](http://fulir.irb.hr/style/images/fileicons/application_pdf.png) |
PDF
- Published Version
- article
Available under License Creative Commons Attribution. Download (9MB) |
Abstract
We report a study of the electronic and nuclear relaxation dynamics of the photoexcited RNA base uracil in the gas phase using time-resolved core-level photoelectron spectroscopy together with high-level calculations. The dynamics was investigated by trajectory surface hopping calculations, and the core ionization energies were calculated for geometries sampled from these. The molecule was excited by a UV laser and dynamics probed on the oxygen, nitrogen, and carbon sites by core electron spectroscopy. We find that the main de-excitation channel of the initially excited S2(pi pi*) state involves internal conversion to the S1(n pi*) state with a time constant of 17 +/- 4 fs, while a portion of S2(pi pi*) population returns directly to the ground state by internal conversion. We find no evidence that the S1(n pi*) state decays to the ground state; instead, it decays to triplet states with a time constant of 1.6 +/- 0.4 ps. Oscillations of the S1(n pi*) state O 1s intensity as a function of time correlate with those of calculated C4=O8 and C5=C6 bond lengths, which undergo a sudden expansion following the initial pi -> pi* excitation. Our calculations support our interpretation of the data and provide detailed insight into the relaxation processes of uracil.
| Item Type: | Article | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Uncontrolled Keywords: | Binding Energy; Chemical Calculations; Excited States; Molecules; Uracil | ||||||||||||
| Subjects: | NATURAL SCIENCES > Chemistry > Theoretical Chemistry | ||||||||||||
| Divisions: | Division of Physical Chemistry | ||||||||||||
| Projects: |
|
||||||||||||
| Depositing User: | Ema Buhin Šaler | ||||||||||||
| Date Deposited: | 26 Feb 2026 13:36 | ||||||||||||
| URI: | http://fulir.irb.hr/id/eprint/11277 | ||||||||||||
| DOI: | 10.1021/jacs.5c04874 |
Actions (login required)
 |
View Item |
Altmetric
Altmetric
