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arXiv · 0902.1164

Physical signatures of discontinuities of the time-dependent exchange-correlation potential

Daniel Vieira·K. Capelle·C. A. Ullrich
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Abstract

The exact exchange-correlation (XC) potential in time-dependent density-functional theory (TDDFT) is known to develop steps and discontinuities upon change of the particle number in spatially confined regions or isolated subsystems. We demonstrate that the self-interaction corrected adiabatic local-density approximation for the XC potential has this property, using the example of electron loss of a model quantum well system. We then study the influence of the XC potential discontinuity in a real-time simulation of a dissociation process of an asymmetric double quantum well system, and show that it dramatically affects the population of the resulting isolated single quantum wells. This indicates the importance of a proper account of the discontinuities in TDDFT descriptions of ionization, dissociation or charge transfer processes.

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Daniel Vieira, K. Capelle, C. A. Ullrich. 2009-02-06. Physical signatures of discontinuities of the time-dependent exchange-correlation potential. https://doi.org/10.1039/b902613d

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