Molecular dynamics
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Mgr. Jiří Pittner Dr. rer. nat.
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We combine ab-initio methods and classical molecular dynamics with surface hopping
(Tully's least switches approach) to study the time-resolved behavior of molecules
in excited states, involving non-adiabatic transitions. The ab-initio potential energy surfaces are not precomputed, but energy, analytic gradient, and
non-adiabatic couplings are computed "on the fly" along the trajectories.
This allows to study molecules with more degrees of freedom.
Since the calculation of non-adiabatic couplings is computationally demanding,
we test also approximate approaches to handle these terms.
We have applied these techniques to non-stoichiometric alkali-halide clusters, for example Na3F.
Example of results: Simulated femtosecond spectrum of Na3F cluster (red) in comparison with the experimental pump-probe spectrum.
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