Electronic Control of InitialNuclear Dynamics Adjacentto a Conical Intersection.

Photoionizationcan create a nonstationary electronic state andtherefore initiates coupled electron–nuclear dynamics in molecules.Using a CASSCF implementation of the Ehrenfest method, we study thenuclear dynamics following vertical ionization of toluene, startingclose to the conical intersection between ground and first excitedstates of its cation. The results show how the initial nuclear dynamicsis controlled by the nonstationary electronic state character. Inparticular, ionization of this system leading to an equal superpositionof the two lowest energy states can initiate nuclear dynamics in anorthogonal direction in the branching space to dynamics on the groundor first excited state potential energy surfaces alone. [ABSTRACT FROM AUTHOR]