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arXiv · 1505.07687

Electron localisation in static and time-dependent one-dimensional model systems

T. R. Durrant·M. J. P. Hodgson·J. D. Ramsden·R. W. Godby
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Abstract

Electron localization is the tendency of an electron in a many-body system to exclude other electrons from its vicinity. Using a new natural measure of localization based on the exact manyelectron wavefunction, we find that localization can vary considerably between different ground-state systems, and can also be strongly disrupted, as a function of time, when a system is driven by an applied electric field. We use our new measure to assess the well-known electron localization function (ELF), both in its approximate single-particle form (often applied within density-functional theory) and its full many-particle form. The full ELF always gives an excellent description of localization, but the approximate ELF fails in time-dependent situations, even when the exact Kohn-Sham orbitals are employed.

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T. R. Durrant, M. J. P. Hodgson, J. D. Ramsden, R. W. Godby. 2015-05-28. Electron localisation in static and time-dependent one-dimensional model systems. https://doi.org/10.1088/1361-648x%2Faaa4cd

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