TY  - JOUR
A1  - Wolf, Thomas J. A.
A1  - Parrish, Robert M.
A1  - Myhre, Rolf H.
A1  - Martinez, Todd J.
A1  - Koch, Henrik
A1  - Gühr, Markus
T1  - Observation of Ultrafast Intersystem Crossing in Thymine by Extreme Ultraviolet Time-Resolved Photoelectron Spectroscopy
T2  - The journal of physical chemistry : A, Molecules, spectroscopy, kinetics, environment & general theory
N2  - We studied the photoinduced ultrafast relaxation dynamics of the nucleobase thymine using gas-phase time-resolved photoelectron spectroscopy. By employing extreme ultraviolet pulses from high harmonic generation for photoionization, we substantially extend our spectral observation window with respect to previous studies. This enables us to follow relaxation of the excited state population all the way to low-lying electronic states including the ground state. In thymine, we observe relaxation from the optically bright (1)pi pi* state of thymine to a dark (1)n pi* state within 80 +/- 30 fs. The (1)n pi* state relaxes further within 3.5 +/- 0.3 ps to a low-lying electronic state. By comparison with quantum chemical simulations, we can unambiguously assign its spectroscopic signature to the (3)pi pi* state. Hence, our study draws a comprehensive picture of the relaxation mechanism of thymine including ultrafast intersystem crossing to the triplet manifold.
Y1  - 2019
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/48476
SN  - 1089-5639
SN  - 1520-5215
VL  - 123
IS  - 32
SP  - 6897
EP  - 6903
PB  - American Chemical Society
CY  - Washington
ER  -