Conical intersection structure and dynamics for a model protonated schiff base photoisomerization in solution

Here, we present some highlights of our recent study [Malhado et al. J. Phys. Chem. A 115, 3729 (2011)] of the photoisomerization involving a conical intersection for a model protonated Schiff base (PSB) in modeled water and acetonitrile solvents, in which the inclusion of energy- and momentum-transfer effects is described via a generalized Langevin equation (GLE) frictional approach and surface-hopping dynamics. Short-time GLE frictional effects on the model's three coordinates, the intramolecular bond length alternation, and torsional PSB coordinates and a solvent coordinate, have a number of important features. Among these are the general feature of accelerating nonadiabatic transitions to the ground electronic state and a predicted preferential higher proportion of ground-state trans isomer, that is, a successful cis to trans photoreaction. This preference is solvent-dependent and is enhanced in water solvent with its higher friction intensity and short time scales. (c) 2012 Wiley Periodicals, Inc.