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arXiv · 2503.10962

The reliability of hybrid functionals for accurate fundamental and optical gap prediction of bulk solids and surfaces

Francisca Sagredo·María Camarasa-Gómez·Francesco Ricci·Aurélie Champagne·Leeor Kronik·Jeffrey B. Neaton
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Abstract

Hybrid functionals have been considered insufficiently reliable for the prediction of band gaps in solids and surfaces. We revisit this issue with a new generation of optimally-tuned range-separated hybrid functionals, focusing on the reconstructed Si(111)-(2x1) and Ge(111)-(2x1) surfaces. We show that certain hybrid functionals can accurately predict the surface-state and bulk fundamental and optical gaps, as well as projected band structures of these surfaces, by combining ground-state and time-dependent density functional theory.

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Francisca Sagredo, María Camarasa-Gómez, Francesco Ricci, Aurélie Champagne, Leeor Kronik, Jeffrey B. Neaton. 2025-03-14. The reliability of hybrid functionals for accurate fundamental and optical gap prediction of bulk solids and surfaces. https://doi.org/10.1021/acs.jctc.5c00160

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