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arXiv · 1004.4850

Dispersion interactions from a local polarizability model

Oleg A. Vydrov·Troy Van Voorhis
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Abstract

A local approximation for dynamic polarizability leads to a nonlocal functional for the long-range dispersion interaction energy via an imaginary-frequency integral. We analyze several local polarizability approximations and argue that the form underlying the construction of our recent van der Waals functional [O. A. Vydrov and T. Van Voorhis, Phys. Rev. Lett. 103, 063004 (2009)] is particularly well physically justified. Using this improved formula, we compute dynamic dipole polarizabilities and van der Waals C_6 coefficients for a set of atoms and molecules. Good agreement with the benchmark values is obtained in most cases.

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Oleg A. Vydrov, Troy Van Voorhis. 2010-06-22. Dispersion interactions from a local polarizability model. https://doi.org/10.1103/physreva.81.062708

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