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Electronic structure and optical properties of quantum crystals from first principles calculations in the Born-Oppenheimer approximation

Authors :
Vitaly Gorelov
David M. Ceperley
Carlo Pierleoni
Markus Holzmann
Laboratoire de physique et modélisation des milieux condensés (LPM2C )
Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)
Maison de la Simulation (MDLS)
Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Holzmann, Markus
Source :
The Journal of Chemical Physics, The Journal of Chemical Physics, AIP, 2020, ⟨10.1063/5.0031843⟩, Journal of Chemical Physics, Journal of Chemical Physics, 2020, ⟨10.1063/5.0031843⟩
Publication Year :
2020
Publisher :
HAL CCSD, 2020.

Abstract

International audience; We develop a formalism to accurately account for the renormalization of electronic structure due to quantum and thermal nuclear motions within the Born-Oppenheimer approximation. We focus on the fundamental energy gap obtained from electronic addition and removal energies from Quantum Monte Carlo calculations in either the canonical or grand canonical ensembles. The formalism applies as well to effective single electron theories such as those based on Density Functional Theory. We show that electronic (Bloch) crystal momentum can be restored by marginalizing the total electron-ion wave function with respect to the nuclear equilibrium distribution, and we describe an explicit procedure to establish the band structure of electronic excitations for quantum crystals within the Born-Oppenheimer approximation. Based on the Kubo-Greenwood equation, we discuss the effects of nuclear motion on optical conductivity. Our methodology applies to the low temperature regime where nuclear motion is quantized and in general differs from the semi-classical approximation. We apply our method to study the electronic structure of C2/c-24 crystalline hydrogen at 200K and 250 GPa and discuss the optical absorption profile of hydrogen crystal at 200K and carbon diamond at 297K.

Details

Language :
English
ISSN :
00219606 and 10897690
Database :
OpenAIRE
Journal :
The Journal of Chemical Physics, The Journal of Chemical Physics, AIP, 2020, ⟨10.1063/5.0031843⟩, Journal of Chemical Physics, Journal of Chemical Physics, 2020, ⟨10.1063/5.0031843⟩
Accession number :
edsair.doi.dedup.....9ef2b4e3a87c494a234696cc752a8337
Full Text :
https://doi.org/10.1063/5.0031843⟩