Born-Oppenheimer approximation additional excited states

In all dynamical simulations presented so far, it has been assumed that the electrons stay in their ground state throughout the whole process, i.e. the simulations have been based on the Born-Oppenheimer approximation. Still, at metal surfaces with their continuous spectrum of electronic states at the Fermi energy electron-hole (e-h) pair excitations with arbitrarily small energies are possible. However, the incorporation of electronically nonadiabatic effects in the dynamical simulation of the interaction dynamics of molecules with surface is rather difficult [2, 109, 110]. Hence the role of electron-hole pairs in the adsorption dynamics as an additional dissipation channel is still unclear [4],... 

Chapter 7 continues the presentation of nonadiabatic electron wavepacket d mamics as applied in various chemical reactions, mainly in electronically excited states. Quantization the branching paths (non-Born-Oppenheimer paths) will be also discussed. Likewise, in Chap. 8, the electron wavepacket dynamics is considered for molecules placed in laser fields. In addition to the ordinary nonadiabatic transitions due to the Born-Oppenheimer approximation, novel nonadiabatic transitions due to optical interactions appear to need special cares. This chapter is to be continued to future studies of laser design of electronic states and concomitant control of chemical reactions. 

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