Excited-State Dynamics of Cytosine Tautomers
Journal of the American Chemical SocietyPublished 29 October 2009
Kyriaki Kosma, Christian Schröter, Elena Samoylova, I. V. Hertel, Thomas Schultz
Citations96
SJR quartileQ1
SJR score5.55
SNIP2.61
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TL;DR
The relaxation dynamics of keto and enol or keto-imino cytosine, photoexcited in the wavelength range of 260-290 nm are reported and three transients with femtosecond to hundreds of picosecond lifetimes are observed for the biologically relevant keto tautomer and assigned to internal conversion and excited-state tautomersization.
Abstract
We report the relaxation dynamics of keto and enol or keto-imino cytosine, photoexcited in the wavelength range of 260-290 nm. Three transients with femtosecond to hundreds of picoseconds lifetimes are observed for the biologically relevant keto tautomer and are assigned to internal conversion and excited-state tautomerization. Only two transients with femtosecond and picosecond lifetimes are identified for the enol or keto-imino tautomer and are assigned to internal conversion processes. The results are discussed in the context of published ab initio theory.
Keywords
Materials ScienceBiochemistry, Genetics and Molecular Biology
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