Molecular dynamics-trajectory surface hopping

Stokes theorem, geometric phase theory, eigenvector evolution, 14-17 Stueckelberg oscillations, direct molecular dynamics, trajectory surface hopping, 398-399... 

Recently, Garth Jones (UNSW) and his co-workers have described a semi-classical molecular dynamics (MD) model, which incorporates the trajectory surface hopping (TSH) method, that shows promise in investigating a number of important problems concerning the effects of molecular vibrations on the dynamics of ET reactions, including formally symmetry-forbidden ones. Essentially,... 

Dynamics Method Fully Quantum Quasi-Classical Trajectory Surface Hop Semi-Classical (Ehrenfest) Molecular Mechanics... 

The very nature of the photochemical processes the multi-state multiconfigurational character and the occurrence of non-adiabatic behavior -leads to the fact that the field of computational photochemistry is still far from saturated with respect to computational tools and method developments. The need to treat several excited states, of different electronic character (covalent, ionic, charge-transfer, Rydberg, etc.), without bias requires the applied theory to be developed at a rather high level of sophistication. While TD-DFT to a large extent is attractable for Born-Oppenheimer molecular dynamics and trajectory surface hopping (TSH), due to its speed, it has its limitations in what type of transitions are correctly... 

A further complexity in the simulation of photochemistry and more in general of excited state photoinduced dynamics is that they are intrinsically nonadiabatic processes, in which the coupling between the nuclear and electronic motion leads to nonradialive transitions between electronic states. A generally applicable approach for this purpose is the mixed quantum-classical dynamics in which the nuclear motion is described by classical trajectories obtained in the framework of molecular dynamics on the fly combined with Tully s surface hopping (TSH) procedure... 

Therefore, we present here our semiclassical Field-Induced Surface Hopping (FISH) method [59] for the simulation and control of the laser-driven coupled electron-nuclear dynamics in complex molecular systems including all degrees of freedom. It is based on the combination of quantum electronic state population dynamics with classical nuclear dynamics carried out on the fly . The idea of the method is to propagate independent trajectories in the manifold of adiabatic electronic states and allow them to switch between the states under the influence of the laser field. The switching probabilities are calculated fully quantum mechanically. The application of our FISH method will be illustrated in Sect. 17.6 on the example of optimal dynamic discrimination (ODD) of two almost identical flavin molecules. 

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