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Published on: August 22, 2019
The Effect of Methylation on the Triplet-State Dynamics of 2-Thiouracil: Time-Resolved Photoelectron Spectroscopy of
Susanne Ullrich1, Yingqi Qu1, Abed Mohamadzade1
1Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602, United States.
Abstract:
The ultrafast internal conversion and intersystem crossing dynamics of 2-thiouracil (2TU) and 2-thiothymine (2TT) are studied using time-resolved photoelectron spectroscopy to investigate the effect of methylation on the deactivation mechanism. Like other thiobases, the triplet manifold is populated with high quantum yields via the lowest singlet excited state, which is dark in absorption. This study focuses on the lowest triplet state and the role of two minima, with sulfur-out-of-plane and slightly boat-like geometries, in the intersystem crossing dynamics back to the ground state.
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