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  • Band gaps of crystalline solids from Wannier-localization–based optimal tuning of a screened range-separated hybrid functional
Title: Band gaps of crystalline solids from Wannier-localization–based optimal tuning of a screened range-separated hybrid functional
Accurate prediction of fundamental band gaps of crystalline solid-state systems entirely within density functional theory is a long-standing challenge. Here, we present a simple and inexpensive method that achieves this by means of nonempirical optimal tuning of the parameters of a screened range-separated hybrid functional. The tuning involves the enforcement of an ansatz that generalizes the ionization potential theorem to the removal of an electron from an occupied state described by a localized Wannier function in a modestly sized supercell calculation. The method is benchmarked against experiment for a set of systems ranging from narrow band-gap semiconductors to large band-gap insulators, spanning a range of fundamental band gaps from 0.2 to 14.2 electronvolts (eV), and is found to yield quantitative accuracy across the board, with a mean absolute error of ∼0.1 eV and a maximal error of ∼0.2 eV.  more » « less
Award ID(s):
2015991
NSF-PAR ID:
10301002
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
34
ISSN:
0027-8424
Page Range / eLocation ID:
e2104556118
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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