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arXiv · 2311.08506

Electronic excitation spectra of molecular hydrogen in Phase I from Quantum Monte Carlo and Many-Body perturbation methods

Vitaly Gorelov·Markus Holzmann·David M. Ceperley·Carlo Pierleoni
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Abstract

We study the electronic excitation spectra in solid molecular hydrogen (phase I) at ambient temperature and 5-90 GPa pressures using Quantum Monte Carlo methods and Many-Body Perturbation Theory. In this range, the system changes from a wide gap molecular insulator to a semiconductor, altering the nature of the excitations from localized to delocalized. Computed gaps and spectra agree with experiments, proving the ability to predict accurately band gaps of many-body systems in presence of nuclear quantum and thermal effects.

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Vitaly Gorelov, Markus Holzmann, David M. Ceperley, Carlo Pierleoni. 2023-11-14. Electronic excitation spectra of molecular hydrogen in Phase I from Quantum Monte Carlo and Many-Body perturbation methods. https://arxiv.org/abs/2311.08506

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