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arXiv · 2201.12146

Ehrenfest dynamics implemented in the all-electron package exciting

Ronaldo Rodrigues Pela·Claudia Draxl
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Abstract

Ehrenfest Dynamics combined with real-time time-dependent density functional theory has proven to be a reliable tool to study non-adiabatic molecular dynamics with a reasonable computational cost. Among other possibilities, it allows for assessing in real time electronic excitations generated by ultra-fast laser pulses, as e.g., in pump-probe spectroscopy, and their coupling to the nuclear vibrations even beyond the linear regime. In this work, we present its implementation in the all-electron full-potential package exciting. Three cases are presented as examples: diamond and cubic BN relaxed after an initial lattice distortion, and cubic BN exposed to a laser pulse. Comparison with the Octopus code exhibits good agreement.

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Ronaldo Rodrigues Pela, Claudia Draxl. 2022-01-28. Ehrenfest dynamics implemented in the all-electron package exciting. https://doi.org/10.1088/2516-1075%2Fac7afc

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