Imperial College London
Professor Michael Bearpark

ProfessorMichaelBearpark

Faculty of Natural Sciences, Department of Chemistry

Professor & Director of User Engagement
 
 
 
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Contact

 

+44 (0)20 7594 5727m.bearpark

 
 
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Location

 

110AMolecular Sciences Research HubWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Segarra-Martí:2019:10.1039/c8cp07189f,
author = {Segarra-Martí, J and Tran, T and Bearpark, MJ},
doi = {10.1039/c8cp07189f},
journal = {Physical Chemistry Chemical Physics},
pages = {14322--14330},
title = {Ultrafast and radiationless electronic excited state decay of uracil and thymine cations: computing the effects of dynamic electron correlation},
url = {http://dx.doi.org/10.1039/c8cp07189f},
volume = {21},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - In this article we characterise the radiationless decay of the first few electronic excited states of the cations of DNA/RNA nucleobases uracil and thymine, including the effects of dynamic electron correlation on energies and geometries (optimised with XMS-CASPT2). In both systems, we find that one state of 2n+O and another two of 2π+ character can be populated following photoionisation, and their different minima and interstate crossings are located. We find strong similarities between uracil and thymine cations: with accessible conical intersections suggesting that depopulation of their electronic excited states takes place on ultrafast timescales in both systems, suggesting that they are photostable in agreement with previous theoretical (uracil+) evidence. We find that dynamic electron correlation separates the energy levels of the "3-state" conical intersection (D2/D1/D0)CI previously located with CASSCF for uracil+, which will therefore have a different geometry and higher energy. Simulating the electronic and vibrational absorptions allows us to characterise spectral fingerprints that could be used to monitor these cation photo-processes experimentally.
AU  - Segarra-Martí,J
AU  - Tran,T
AU  - Bearpark,MJ
DO  - 10.1039/c8cp07189f
EP  - 14330
PY  - 2019///
SN  - 1463-9076
SP  - 14322
TI  - Ultrafast and radiationless electronic excited state decay of uracil and thymine cations: computing the effects of dynamic electron correlation
T2  - Physical Chemistry Chemical Physics
UR  - http://dx.doi.org/10.1039/c8cp07189f
UR  - https://www.ncbi.nlm.nih.gov/pubmed/30698175
UR  - https://pubs.rsc.org/en/content/articlelanding/2019/CP/C8CP07189F#!divAbstract
UR  - http://hdl.handle.net/10044/1/67535
VL  - 21
ER  -
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