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arXiv · 1211.2012

Universal Dynamical Steps in the Exact Time-Dependent Exchange-Correlation Potential

Peter Elliott·Johanna I. Fuks·Angel Rubio·Neepa T. Maitra
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Abstract

We show that the exact exchange-correlation potential of time-dependent density-functional theory displays dynamical step structures that have a spatially non-local and time non-local dependence on the density. Using one-dimensional two-electron model systems, we illustrate these steps for a range of non-equilibrium dynamical situations relevant for modeling of photo-chemical/physical processes: field-free evolution of a non-stationary state, resonant local excitation, resonant complete charge-transfer, and evolution under an arbitrary field. Lack of these steps in usual approximations yield inaccurate dynamics, for example predicting faster dynamics and incomplete charge transfer.

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Peter Elliott, Johanna I. Fuks, Angel Rubio, Neepa T. Maitra. 2012-11-08. Universal Dynamical Steps in the Exact Time-Dependent Exchange-Correlation Potential. https://doi.org/10.1103/physrevlett.109.266404

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