title: Non-adiabatic transition probability dependence on conical intersection topography.
abstract: We derive a closed form analytical expression for the non-adiabatic transition probability for a distribution of trajectories passing through a generic conical intersection (CI), based on the Landau-Zener equation for the non-adiabatic transition probability for a single straight-line trajectory in the CI's vicinity. We investigate the non-adiabatic transition probability's variation with topographical features and find, for the same crossing velocity, no intrinsic difference in efficiency at promoting non-adiabatic decay between peaked and sloped CIs, a result in contrast to the commonly held view. Any increased efficiency of peaked over sloped CIs is thus due to dynamical effects rather than to any increased transition probability of topographical origin. It is also shown that the transition probability depends in general on the direction of approach to the CI, and that the coordinates' reduced mass can affect the transition probability via its influence on the CI topography in mass-scaled coordinates. The resulting predictions compare well with surface hopping simulation results.
authors.affiliation: Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom.
authors.forename: João Pedro
authors.initials: JP
authors.lastname: Malhado
authors.affiliation: Department of Chemistry, École Normale Supérieure-PSL Research University, Sorbonne Universités-UPMC University Paris 06, CNRS UMR 8640 Pasteur, 24 rue Lhomond, 75005 Paris, France.
authors.forename: James T
authors.initials: JT
authors.lastname: Hynes