Challenges with relativistic GW calculations in solids and molecules

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Harsha, Gaurav, Abraham, Vibin, Zgid, Dominika
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866909848592973824
author Harsha, Gaurav
Abraham, Vibin
Zgid, Dominika
author_facet Harsha, Gaurav
Abraham, Vibin
Zgid, Dominika
contents For molecules and solids containing heavy elements, accurate electronic structure calculations require accounting not only for electronic correlations but also for relativistic effects. In molecules, relativity can lead to severe changes in the ground-state description. In solids, the interplay between both correlation and relativity can change the stability of phases or it can lead to an emergence of completely new phases. Traditionally, the simplest illustration of relativistic effects can be done either by including pseudopotentials in non-relativistic calculations or alternatively by employing large all electron basis sets in relativistic methods. By analyzing different electronic properties (band structure, equilibrium lattice constant and bulk modulus) in semiconductors and insulators, we show that capturing the interplay of relativity and electron correlation can be rather challenging in Green's function methods. For molecular problems with heavy elements, we also observe that similar problems persist. We trace these challenges to three major problems: deficiencies in pseudopotential treatment as applied to Green's function methods, the scarcity of accurate and compact all-electron basis-sets that can be converged with respect to the basis-set size, and linear dependencies arising in all-electron basis-sets particularly when employing Gaussian orbitals. Our analysis provides detailed insight into these problems and opens a discussion about potential approaches to mitigate them.
format Preprint
id arxiv_https___arxiv_org_abs_2403_03961
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Challenges with relativistic GW calculations in solids and molecules
Harsha, Gaurav
Abraham, Vibin
Zgid, Dominika
Chemical Physics
Strongly Correlated Electrons
For molecules and solids containing heavy elements, accurate electronic structure calculations require accounting not only for electronic correlations but also for relativistic effects. In molecules, relativity can lead to severe changes in the ground-state description. In solids, the interplay between both correlation and relativity can change the stability of phases or it can lead to an emergence of completely new phases. Traditionally, the simplest illustration of relativistic effects can be done either by including pseudopotentials in non-relativistic calculations or alternatively by employing large all electron basis sets in relativistic methods. By analyzing different electronic properties (band structure, equilibrium lattice constant and bulk modulus) in semiconductors and insulators, we show that capturing the interplay of relativity and electron correlation can be rather challenging in Green's function methods. For molecular problems with heavy elements, we also observe that similar problems persist. We trace these challenges to three major problems: deficiencies in pseudopotential treatment as applied to Green's function methods, the scarcity of accurate and compact all-electron basis-sets that can be converged with respect to the basis-set size, and linear dependencies arising in all-electron basis-sets particularly when employing Gaussian orbitals. Our analysis provides detailed insight into these problems and opens a discussion about potential approaches to mitigate them.
title Challenges with relativistic GW calculations in solids and molecules
topic Chemical Physics
Strongly Correlated Electrons
url https://arxiv.org/abs/2403.03961