title: Critical appraisal of excited state nonadiabatic dynamics simulations of 9H-adenine.
abstract: In spite of the importance of nonadiabatic dynamics simulations for the understanding of ultrafast photo-induced phenomena, simulations based on different methodologies have often led to contradictory results. In this work, we proceed through a comprehensive investigation of on-the-fly surface-hopping simulations of 9H-adenine in the gas phase using different electronic structure theories (ab initio, semi-empirical, and density functional methods). Simulations that employ ab initio and semi-empirical multireference configuration interaction methods predict the experimentally observed ultrafast deactivation of 9H-adenine with similar time scales, however, through different internal conversion channels. Simulations based on time-dependent density functional theory with six different hybrid and range-corrected functionals fail to predict the ultrafast deactivation. The origin of these differences is analyzed by systematic calculations of the relevant reaction pathways, which show that these discrepancies can always be traced back to topographical features of the underlying potential energy surfaces.
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim, Germany. barbatti@kofo.mpg.de
authors.forename: Mario
authors.initials: M
authors.lastname: Barbatti
authors.forename: Zhenggang
authors.initials: Z
authors.lastname: Lan
authors.forename: Rachel
authors.initials: R
authors.lastname: Crespo-Otero
authors.forename: Jaroslaw J
authors.initials: JJ
authors.lastname: Szymczak
authors.forename: Hans
authors.initials: H
authors.lastname: Lischka
authors.forename: Walter
authors.initials: W
authors.lastname: Thiel
mesh_terms: D000225:Adenine / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory
chemical_list: D000225:Adenine