Excited-State Relaxation of Hydrated Thymine and Thymidine Measured by Liquid-Jet Photoelectron Spectroscopy: Experiment and Simulation

• Buchner, Franziska

• Nakayama, Akira

• Yamazaki, Shohei

• Ritze, Hans-Hermann

• Luebcke, Andrea

Abstract

Time-resolved photoelectron spectroscopy is performed on thymine and thymidine in aqueous solution to study the excited-state relaxation dynamics of these molecules. We find two contributions with sub-ps lifetimes in line with recent excited-state QM/MM molecular dynamics simulations (J. Chem. Phys. 2013, 139, 214304). The temporal evolution of ionization energies for the excited pi pi* state along the QM/MM molecular dynamics trajectories were calculated and are compatible with experimental results, where the two contributions correspond to the relaxation paths in the pi pi* state involving different conical intersections with the ground state. Theoretical calculations also show that ionization from the n pi* state is possible at the given photon energies, but we have not found any experimental indication for signal from the n pi* state. In contrast to currently accepted relaxation mechanisms, we suggest that the n pi* state is not involved in the relaxation process of thymine in aqueous solution.

Journal

• Journal of the American Chemical Society

  Journal of the American Chemical Society 137 (8), 2931-2938, 2015-03-05

  American Chemical Society

Keywords

• Colloid and Surface Chemistry
• Biochemistry
• General Chemistry
• Catalysis

Details

• CRID: 1050564288971575424
• NII Article ID: 120005603806
• DOI: 10.1021/ja511108u
• ISSN: 15205126
• ISSN: 00027863
• HANDLE: 2115/58853
• Web Site: https://pubs.acs.org/doi/pdf/10.1021/ja511108u
• Text Lang: en
• Article Type: journal article
• Data Source:
  • IRDB
  • Crossref
  • CiNii Articles
  • KAKEN