JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, v.131, no.46, pp.16939 - 16943
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 picosends 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.