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arXiv · 1703.08786

A fractionally ionic approach to polarizability and van der Waals many-body dispersion calculations

Tim Gould·Sébastien Lebègue·János G. Ángyán·Tomáš Bučko
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Abstract

By explicitly including fractionally ionic contributions to the polarizability of a many-component system we are able to significantly improve on previous atom-wise many-body van der Waals approaches with essentially no extra numerical cost. For non-ionic systems our method is comparable in accuracy to existing approaches. However, it offers substantial improvements in ionic solids, e.g. producing better polarizabilities by over 65% in some cases. It has particular benefits for two-dimensional transition metal dichalcogenides, and interactions of H$_2$ with modified coronenes - ionic systems of nanotechnological interest. It thus offers an efficient improvement on existing approaches, valid for a wide range of systems.

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Tim Gould, Sébastien Lebègue, János G. Ángyán, Tomáš Bučko. 2017-03-26. A fractionally ionic approach to polarizability and van der Waals many-body dispersion calculations. https://doi.org/10.1021/acs.jctc.6b00925

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