Real-time observation of intramolecular proton transfer in the electronic ground state of chloromalonaldehyde: an ab initio study of time-resolved photoelectron spectra.
The authors report on studies of time-resolved photoelectron spectra of intramolecular proton transfer in the ground state of chloromalonaldehyde, employing ab initio photoionization matrix elements and effective potential surfaces of reduced dimensionality, wherein the couplings of proton motion to the other molecular vibrational modes are embedded by averaging over classical trajectories. In the simulations, population is transferred from the vibrational ground state to vibrationally hot wave packets by pumping to an excited electronic state and dumping with a time-delayed pulse. These pump-dump-probe simulations demonstrate that the time-resolved photoelectron spectra track proton transfer in the electronic ground state well and, furthermore, that the geometry dependence of the matrix elements enhances the tracking compared with signals obtained with the Condon approximation. Photoelectron kinetic energy distributions arising from wave packets localized in different basins are also distinguishable and could be understood, as expected, on the basis of the strength of the optical couplings in different regions of the ground state potential surface and the Franck-Condon overlaps of the ground state wave packets with the vibrational eigenstates of the ion potential surface.
do N Varella
Márcio T
MT
Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Tokyo 153-8902, Japan.
Arasaki
Yasuki
Y
Ushiyama
Hiroshi
H
Takatsuka
Kazuo
K
Wang
Kwanghsi
K
McKoy
Vincent
V
D004583:Electrons; D004735:Energy Transfer; D007700:Kinetics; D008315:Malondialdehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D008954:Models, Biological; D008968:Molecular Conformation; D010777:Photochemistry; D011522:Protons; D013057:Spectrum Analysis
D011522:Protons; C083258:chloromalonaldehyde; D008315:Malondialdehyde