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DOE OSTI · 3001813

Range-separated thermal hybrid exchange-correlation density functional for accurate band-gap calculations of warm dense matter

Ellaboudy, Ammar A. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000176894336)·Karasiev, Valentin V. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000334456797)·Mihaylov, Deyan I. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000288745503)·Hilleke, Katerina P. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000343228403)·Hu, S. X. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000324653818)
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Abstract

Here, in this study, we present a range-separated thermal hybrid exchange-correlation (XC) functional, termed RS-KDT0, which provides highly accurate band-gap predictions at elevated temperature while reducing the computational cost relative to thermal global hybrid functionals. At zero temperature, RS-KDT0 recovers the widely used ground-state range-separated hybrid functional HSE06. To assess its performance across temperature regimes, we conducted static calculations of electronic pressure, band gaps, and band structures. RS-KDT0 exhibits the same level of accuracy as HSE06 in the low-temperature regime and demonstrates improved agreement with finite-temperature GW calculations at elevated temperatures when compared to other thermal XC functionals such as the generalized gradient approximation (GGA)-level KDT16 and the global hybrid KDT0.

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Ellaboudy, Ammar A. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000176894336), Karasiev, Valentin V. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000334456797), Mihaylov, Deyan I. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000288745503), Hilleke, Katerina P. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000343228403), Hu, S. X. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics] (ORCID:0000000324653818). 2025-10-24. Range-separated thermal hybrid exchange-correlation density functional for accurate band-gap calculations of warm dense matter. https://doi.org/10.1103/v9vy-x124

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