Nonempirical Range-separated Hybrid Functionals for Solids and Molecules

TL;DR

This paper introduces a non-empirical range-separated hybrid functional approach that improves the accuracy of electronic property predictions for solids and molecules while maintaining computational efficiency.

Contribution

The paper develops a range-separated dielectric-dependent hybrid functional with system-dependent parameters, enhancing accuracy for solids and molecules.

Findings

Accurate energy gaps and dielectric constants for solids

Effective for inorganic and organic materials

Applicable to finite systems

Abstract

Dielectric-dependent hybrid (DDH) functionals were recently shown to yield accurate energy gaps and dielectric constants for a wide variety of solids, at a computational cost considerably less than that of GW calculations. The fraction of exact exchange included in the definition of DDH functionals depends (self-consistently) on the dielectric constant of the material. Here we introduce a range-separated (RS) version of DDH functionals where short and long-range components are matched using system dependent, non-empirical parameters. We show that RS DDHs yield accurate electronic properties of inorganic and organic solids, including energy gaps and absolute ionization potentials. Furthermore we show that these functionals may be generalized to finite systems.