title: Communication: GAIMS--Generalized Ab Initio Multiple Spawning for both internal conversion and intersystem crossing processes.
abstract: Full multiple spawning is a formally exact method to describe the excited-state dynamics of molecular systems beyond the Born-Oppenheimer approximation. However, it has been limited until now to the description of radiationless transitions taking place between electronic states with the same spin multiplicity. This Communication presents a generalization of the full and ab initio multiple spawning methods to both internal conversion (mediated by nonadiabatic coupling terms) and intersystem crossing events (triggered by spin-orbit coupling matrix elements) based on a spin-diabatic representation. The results of two numerical applications, a model system and the deactivation of thioformaldehyde, validate the presented formalism and its implementation.
authors.affiliation: Department of Chemistry and the PULSE Institute, Stanford University, Stanford, California 94305, USA.
authors.forename: Basile F E
authors.initials: BF
authors.lastname: Curchod
authors.affiliation: Institute of Theoretical Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
authors.forename: Clemens
authors.initials: C
authors.lastname: Rauer
authors.affiliation: Institute of Theoretical Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Marquetand
authors.affiliation: Institute of Theoretical Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria.
authors.forename: Leticia
authors.initials: L
authors.lastname: González
authors.affiliation: Department of Chemistry and the PULSE Institute, Stanford University, Stanford, California 94305, USA.
authors.forename: Todd J
authors.initials: TJ
authors.lastname: Martínez