Photoinduced processes in thiouracil derivatives have lately attracted considerable attention due to their suitability for innovative biological and pharmacological applications. Here, sub-20 fs broadband transient absorption spectroscopy in the near-UV are combined with CASPT2/MM decay path calculations to unravel the excited-state decay channels of water solvated 2-thio and 2,4-dithiouracil. These molecules feature linear absorption spectra with overlapping ππ* bands, leading to parallel decay routes which we systematically track for the first time. The results reveal that different processes lead to the triplet states population, both directly from the ππ* absorbing state and via the intermediate nπ* dark state. Moreover, the 2,4-dithiouracil decay pathways is shown to be strongly correlated either to those of 2- or 4-thiouracil, depending on the sulfur atom on which the electronic transition localizes.

Teles-Ferreira D.C., Conti I., Borrego-Varillas R., Nenov A., Van Stokkum I.H.M., Ganzer L., et al. (2020). A Unified Experimental/Theoretical Description of the Ultrafast Photophysics of Single and Double Thionated Uracils. CHEMISTRY-A EUROPEAN JOURNAL, 26(1), 336-343 [10.1002/chem.201904541].

A Unified Experimental/Theoretical Description of the Ultrafast Photophysics of Single and Double Thionated Uracils

Conti I.;Nenov A.;de Paula A. M.;Garavelli M.
2020

Abstract

Photoinduced processes in thiouracil derivatives have lately attracted considerable attention due to their suitability for innovative biological and pharmacological applications. Here, sub-20 fs broadband transient absorption spectroscopy in the near-UV are combined with CASPT2/MM decay path calculations to unravel the excited-state decay channels of water solvated 2-thio and 2,4-dithiouracil. These molecules feature linear absorption spectra with overlapping ππ* bands, leading to parallel decay routes which we systematically track for the first time. The results reveal that different processes lead to the triplet states population, both directly from the ππ* absorbing state and via the intermediate nπ* dark state. Moreover, the 2,4-dithiouracil decay pathways is shown to be strongly correlated either to those of 2- or 4-thiouracil, depending on the sulfur atom on which the electronic transition localizes.
2020
Teles-Ferreira D.C., Conti I., Borrego-Varillas R., Nenov A., Van Stokkum I.H.M., Ganzer L., et al. (2020). A Unified Experimental/Theoretical Description of the Ultrafast Photophysics of Single and Double Thionated Uracils. CHEMISTRY-A EUROPEAN JOURNAL, 26(1), 336-343 [10.1002/chem.201904541].
Teles-Ferreira D.C.; Conti I.; Borrego-Varillas R.; Nenov A.; Van Stokkum I.H.M.; Ganzer L.; Manzoni C.; de Paula A.M.; Cerullo G.; Garavelli M.
File in questo prodotto:
File Dimensione Formato  
Conti_Garavelli_postprint_2020 (1).pdf

Open Access dal 03/01/2021

Tipo: Postprint
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione - Non commerciale (CCBYNC)
Dimensione 6.13 MB
Formato Adobe PDF
6.13 MB Adobe PDF Visualizza/Apri
Supplementare_Conti_chem201904541-sup-0001-misc_information.pdf

accesso aperto

Tipo: File Supplementare
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione - Non commerciale (CCBYNC)
Dimensione 2.99 MB
Formato Adobe PDF
2.99 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/732451
Citazioni
  • ???jsp.display-item.citation.pmc??? 11
  • Scopus 32
  • ???jsp.display-item.citation.isi??? 27
social impact