Relativistic coupled-cluster and equation-of-motion coupled-cluster methods

• Main Authors: Cheng, L. (Author), Liu, J. (Author)
• Format: Article
• Language: English
• Published: John Wiley and Sons Inc 2021
• Subjects: Ab initio electronic structure methods; Calculations; Chemical elements; Cluster analysis; Computation theory; Computational efficiency; Core-excited state; coupled cluster theory; Coupled clusters; coupled-cluster method; Electronic ground state; Electronic structure; electronic structure theory; Electronic structure theory; equation of motion coupled cluster methods; Equation of motion coupled clusters; Equations of motion; exact two-component theory; Excited states; Ground state; Heavy elements; Numerical methods; Perturbative treatment; relativistic effects; relativistic quantum chemistry; Spin orbit coupling; spin-orbit coupling
• Online Access: View Fulltext in Publisher
• ISBN: 17590876 (ISSN)
• DOI: 10.1002/wcms.1536

The development of relativistic coupled-cluster (CC) and equation-of-motion coupled-cluster (EOM-CC) methods is reviewed. An emphasis is placed on recent efforts to improve the computational efficiency of CC and EOM-CC calculations with non-perturbative treatments of spin-orbit coupling (SO-CC and EOM-CC) by partially recovering spin symmetry in the formulations. Example calculations of electronic ground state as well as valence-excited and core-excited states for molecules containing heavy elements are presented to demonstrate the applicability and usefulness of the SO-CC and EOM-CC methods. Future directions for the development of the SO-CC and EOM-CC methods are also discussed. This article is categorized under: Electronic Structure Theory > Ab Initio Electronic Structure Methods. © 2021 The Authors. WIREs Computational Molecular Science published by Wiley Periodicals LLC.