title: Surface Hopping Dynamics with Correlated Single-Reference Methods: 9H-Adenine as a Case Study.
abstract: Surface hopping dynamics methods using the coupled cluster to approximated second order (CC2), the algebraic diagrammatic construction scheme to second order (ADC(2)), and the time-dependent density functional theory (TDDFT) were developed and implemented into the program system Newton-X. These procedures are especially well-suited to simulate nonadiabatic processes involving various excited states of the same multiplicity and the dynamics in the first excited state toward an energetic minimum or up to the region where a crossing with the ground state is found. 9H-adenine in the gas phase was selected as the test case. The results showed that dynamics with ADC(2) is very stable, whereas CC2 dynamics fails within 100 fs, because of numerical instabilities present in the case of quasi-degenerate excited states. ADC(2) dynamics correctly predicts the ultrafast character of the deactivation process. It predicts that C2-puckered conical intersections should be the preferential pathway for internal conversion for low-energy excitation. C6-puckered conical intersection also contributes appreciably to internal conversion, becoming as important as C2-puckered for high-energy excitations. In any case, H-elimination plays only a minor role. TDDFT based on a long-range corrected functional fails to predict the ultrafast deactivation. In the comparison with several other methods previously used for dynamics simulations of adenine, ADC(2) has the best performance, providing the most consistent results so far.
authors.affiliation: Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University , Im Neuenheimer Feld 368, 69120 Heidelberg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Plasser
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
authors.forename: Rachel
authors.initials: R
authors.lastname: Crespo-Otero
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic , v.v.i., Dolejškova 3, 18223 Prague 8, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Pederzoli
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic , v.v.i., Dolejškova 3, 18223 Prague 8, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Pittner
authors.affiliation: Department of Chemistry and Biochemistry, Texas Tech University , Lubbock, Texas 79409-1061, United States.|Institute for Theoretical Chemistry, University of Vienna , Währingerstr. 17, A-1090 Vienna, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Lischka
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Barbatti