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arXiv · 2308.03991

Nonempirical Range-Separated Hybrid Functional with Spatially Dependent Screened Exchange

Jiawei Zhan·Marco Govoni·Giulia Galli
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Abstract

Electronic structure calculations based on Density Functional Theory have successfully predicted numerous ground state properties of a variety of molecules and materials. However, exchange and correlation functionals currently used in the literature, including semi-local and hybrid functionals, are often inaccurate to describe the electronic properties of heterogeneous solids, especially systems composed of building blocks with large dielectric mismatch. Here, we present a dielectric-dependent range-separated hybrid functional, SE-RSH, for the investigation of heterogeneous materials. We define a spatially dependent fraction of exact exchange inspired by the static Coulomb-hole and screened-exchange (COHSEX) approximation used in many body perturbation theory, and we show that the proposed functional accurately predicts the electronic structure of several non-metallic interfaces, three- and two-dimensional, pristine and defective solids and nanoparticles.

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Jiawei Zhan, Marco Govoni, Giulia Galli. 2023-08-08. Nonempirical Range-Separated Hybrid Functional with Spatially Dependent Screened Exchange. https://arxiv.org/abs/2308.03991

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