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Exact Kohn-Sham exchange kernel for insulators and its long-wavelength behavior

Yong-Hoon Kim·Andreas Goerling
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Abstract

We present an exact expression for the frequency-dependent Kohn-Sham exact-exchange (EXX) kernel for periodic insulators, which can be employed for the calculation of electronic response properties within time-dependent (TD) density-functional theory. It is shown that the EXX kernel has a long-wavelength divergence behavior of the exact full exchange-correlation kernel and thus rectifies one serious shortcoming of the adiabatic local-density approximation and generalized-gradient approximations kernels. A comparison between the TDEXX and the GW-approximation-Bethe-Salpeter-equation approach is also made.

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Yong-Hoon Kim, Andreas Goerling. 2002-05-28. Exact Kohn-Sham exchange kernel for insulators and its long-wavelength behavior. https://doi.org/10.1103/physrevb.66.035114

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