Electronic excitation spectra of molecular hydrogen in phase I from quantum Monte Carlo and many-body perturbation methods

POSTER

Abstract

In this talk, I will present the electronic excitations in solid molecular hydrogen at room temperature and pressures ranging from 5 to 90 GPa, calculated using quantum Monte Carlo methods and many-body perturbation theory. Our results reveal a crossover from a wide-gap insulator to a semiconductor, illustrating a shift in the nature of excitations from localized molecular to delocalized states. Based on the computed energy gaps and optical properties, I will discuss and interpret recent inelastic X-ray scattering (IXS) experimental results [1]. This work demonstrates the capability of accurately predicting band gaps in many-body systems with strong zero-point and thermal effects [2].

[1] B. Li, et al, PRL 126, 036402 (2021)

[2] V. Gorelov et al, PRB 109, L241111 (2024)

*M.H. acknowledges support from the French Agency via research project SIX (ANR-23-CE30- 0022). D.M.C. is supported by U.S. DOE Grant No. DE-SC0020177. C.P. was supported by the European Union - NextGenerationEU under the Italian Ministry of University and Research (MUR), Projects PRIN2022-2022NRBLPT, CUP E53D23001790006, PRIN2022-P2022MC742PNRR, CUP E53D23018440001. This research used HPC resources from GENCI-IDRIS 2022-AD010912502R1 and 2023-A0140914158 and GENCI (Project No. 544) and the GRICAD infrastructure supported by Grenoble research communities.

Publication: [2] Vitaly Gorelov, Markus Holzmann, David M. Ceperley, and Carlo Pierleoni, Electronic excitation spectra of molecular hydrogen in phase I from quantum Monte Carlo and many-body perturbation methods, Phys. Rev. B 109, L241111 (2024) https://doi.org/10.1103/PhysRevB.109.L241111

Presenters

  • Vitaly Gorelov

    • CNRS, Ecole Polytechnique

Authors

  • Vitaly Gorelov

    • CNRS, Ecole Polytechnique

  • David M Ceperley

    • University of Illinois at Urbana-Champaign

  • Markus Holzmann

    • Univ. Grenoble Alpes, CNRS, LPMMC, 38000 Grenoble, France
    • CNRS

  • CARLO PIERLEONI

    • Univ of L'Aquila