PHYS 612 |
| The excited-state intramolecular proton-transfer dynamics and spectroscopy associated with the ketoenolic tautomerization reaction in 2-(2-hydroxyphenyl)-benzothiazole are simulated according to a numerically exact quantum-dynamics propagation method and a full-dimensional excited-state potential energy surface, based on an ab initio reaction surface Hamiltonian. The reported simulations involve the propagation of 69-dimensional wave packets according to the matching-pursuit / split-operator-Fourier-transform (MP/SOFT) method [J. Chem. Phys. 121, 1676, 2004]. The underlying propagation scheme recursively applies the time-evolution operator as defined by the Trotter expansion to second order accuracy in dynamically adaptive coherent-state expansions. Computations of time-dependent survival amplitudes, photoabsorption cross sections, and time-dependent reactant(product) populations are compared to the corresponding calculations based on the time-dependent self-consistent field method. The reported results demonstrate the capabilities of the MP/SOFT method as a valuble computational tool to study ultrafast reaction dynamics in polyatomic systems as well as to validate simulations of complex(nonintegrable) quantum dynamics in multidimensional model systems by approximate methods. |
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PHYS Poster Session - Computational Spectroscopy and Reaction Dynamics
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Division of Physical Chemistry |