An Accurate Alternative to Hybrid Functionals for Germanium: DFT+α.

ABSTRACT: The accuracy of bulk-property predictions in density functional theory (DFT) calculations depends on the choice of the exchange-correlation functional. While the Perdew-Burke-Ernzerhof (PBE) functional systematically overestimates lattice parameters and strongly underestimates electronic band gaps, hybrid functionals such as Heyd-Scuseria-Ernzerhof (HSE) offer better overall agreement across a broad range of materials. Using germanium as a critical test case, we challenge the ability of both functionals to capture the semiconductor properties. Although HSE improves PBE's gap error, it fails to reproduce germanium's correct Γ-L indirect and Γ-Γ band gaps simultaneously. Noting that the PBE-underestimated energy separation between the 4p valence-band maximum and 4s conduction-band minimum ca

SUBMITTER: Abdurrazaq A 

PROVIDER: S-EPMC12833989 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature