Document Detail


Photoinduced Formation Mechanism of the Thymine-Thymine (6-4) Adduct.
MedLine Citation:
PMID:  23339629     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The photoinduced mechanism leading to the formation of the thymine-thymine (6-4) photolesion has been studied by using the CASPT2//CASSCF approach over a dinucleotide model in vacuo. Following light absorption, localization of the excitation on a single thymine leads to fast singlet-triplet crossing that populates the triplet 3(nπ*) state of thymine. This state, displaying an elongated C4=O bond, triggers (6-4) dimer formation by reaction with the C5=C6 double bond of the adjacent thymine, followed by a second intersystem crossing which acts as a gate between the excited state of the reactant and the ground state of the photoproduct. The requirement of localized excitation on just one thymine, whose main decay channel (by radiationless repopulation of its ground state) is non-photochemical, can rationalize the experimentally observed low quantum yield of formation for the thymine-thymine (6-4) adduct.
Authors:
Angelo Giussani; Luis Serrano-Andres; Manuela Merchan; Daniel Roca-Sanjuán; Marco Garavelli
Related Documents :
17501119 - Electron collisions with formic acid monomer and dimer.
18517239 - Infrared spectra of a model phenol-amine proton transfer complex in nanoconfined ch3cl.
16803259 - Mixed wannier-bloch functions for electrons and phonons in periodic systems.
15332919 - Vibrational dynamics of adsorbed molecules under conditions of photodesorption: pump-pr...
24562049 - Controlled fabrication of porous double-walled tio2 nanotubes via ultraviolet-assisted ...
18044869 - Vibrational energy relaxation of the bend fundamental of dilute water in liquid chlorof...
20609619 - The electronic locum record for general practitioners: outcome of an evaluation study i...
7976949 - Fast spin-echo imaging of the neck: comparison with conventional spin-echo, utility of ...
23126809 - A portable molecular beam epitaxy system for in situ x-ray investigations at synchrotro...
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2013-1-23
Journal Detail:
Title:  The journal of physical chemistry. B     Volume:  -     ISSN:  1520-5207     ISO Abbreviation:  J Phys Chem B     Publication Date:  2013 Jan 
Date Detail:
Created Date:  2013-1-23     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101157530     Medline TA:  J Phys Chem B     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Where on earth to publish? A sample survey comparing traditional and open access publishing in the o...
Next Document:  Characterization of HIV-1 gag and nef in Cameroon: further evidence of extreme diversity at the orig...