| Abstract
| - The proton-transfer dynamics in the aromatic Schiff base salicylidene methylamine has been theoreticallyanalyzed in the ground and first singlet (π,π*) excited electronic states by density functional theory calculationsand quantum wave-packet dynamics. The potential energies obtained through electronic calculations that usethe time-dependent density functional theory formalism, which predict a barrierless excited-state intramolecularproton transfer, are fitted to a reduced three-dimensional potential energy surface. The time evolution in thissurface is solved by means of the multiconfiguration time-dependent Hartree algorithm applied to solve thetime-dependent Schrödinger equation. It is shown that the excited-state proton transfer occurs within 11 fsfor hydrogen and 25 fs for deuterium, so that a large kinetic isotope effect is predicted. These results arecompared to those of the only previous theoretical work published on this system [Zgierski, M. Z.; Grabowska,A. J. Chem. Phys.2000, 113, 7845], reporting a configuration interaction singles barrier of 1.6 kcal mol-1and time reactions of 30 and 115 fs for the hydrogen and deuterium transfers, respectively, evaluated withthe semiclassical instanton approach.
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