Exploring the accuracy of the equation-of-motion coupled-cluster band gap of solids

Autor(en)

Evgeny Moerman, Henrique Miranda, Alejandro Gallo, Andreas Irmler, Tobias Schäfer, Felix Hummel, Manuel Engel, Georg Kresse, Matthias Scheffler, Andreas Grüneis

Abstrakt

While the periodic equation-of-motion coupled-cluster (EOM-CC) method promises systematic improvement of electronic band gap calculations in solids, its practical application at the singles and doubles level (EOM-CCSD) is hindered by severe finite-size errors in feasible simulation cells. We present a hybrid approach combining EOM-CCSD with the computationally less demanding GW approximation to estimate thermodynamic limit band gaps for several insulators and semiconductors. Our method substantially reduces required cell sizes while maintaining accuracy. Comparisons with experimental gaps and self-consistent GW calculations reveal that deviations in EOM-CCSD predictions correlate with reduced single excitation character of the excited many-electron states. Our work not only provides a computationally tractable approach to EOM-CC calculations in solids but also reveals fundamental insights into the role of single excitations in electronic-structure theory.

Organisation(en)

Computergestützte Materialphysik

Externe Organisation(en)

Fritz-Haber-Institut der Max-Planck-Gesellschaft, VASP Software GmbH, Technische Universität Wien

Journal

Physical Review B

Band

111

Anzahl der Seiten

7

ISSN

2469-9950

DOI

https://doi.org/10.48550/arXiv.2501.18667

Publikationsdatum

03-2025

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik, 103015 Kondensierte Materie

ASJC Scopus Sachgebiete

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/ecdef07d-a4bc-4d7b-9b39-32f855a5f8de