title: Mechanism of Ultrafast Photodecay in Restricted Motions in Protonated Schiff Bases: The Pentadieniminium Cation.
abstract: Ab initio surface-hopping dynamics simulations for the trans-penta-3,5-dieniminium cation (PSB3) are presented imposing different sets of mechanical restrictions in order to investigate the response of the molecular system to certain environmental degrees of hindrance. A general scheme for classification of photoisomerization mechanisms in conjugated chains based on the analysis of torsional angles is proposed allowing direct characterization of the different isomerization mechanisms proposed previously. On the basis of a statistical analysis of 300 trajectories a new photoisomerization mechanism-the Folding Table-was found. This mechanism and the One-Bond-Flip are almost entirely responsible for the photoisomerization process in PSB3.
authors.affiliation: Institute for Theoretical Chemistry, University of Vienna, Waehringerstrasse 17, A-1090 Vienna, Austria.
authors.forename: Jaroslaw J
authors.initials: JJ
authors.lastname: Szymczak
authors.affiliation: Institute for Theoretical Chemistry, University of Vienna, Waehringerstrasse 17, A-1090 Vienna, Austria.
authors.forename: Mario
authors.initials: M
authors.lastname: Barbatti
authors.affiliation: Institute for Theoretical Chemistry, University of Vienna, Waehringerstrasse 17, A-1090 Vienna, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Lischka