English

Describing Strong Correlation with Block-Correlated Coupled Cluster Theory

Chemical Physics 2023-03-16 v1

Abstract

A block-correlated coupled cluster (BCCC) method based on the generalized valence bond (GVB) wave function (GVB-BCCC in short) is proposed and implemented at the ab initio level, which represents an attractive multireference electronic structure method for strongly correlated systems. The GVB-BCCC method is demonstrated to provide accurate descriptions for multiple bond breaking in small molecules, although the GVB reference function is qualitatively wrong for the studied processes. For a challenging prototype of strongly correlated systems, tridecane with all 12 single C-C bonds at various distances, our calculations have shown that the GVB-BCCC2b method can provide highly comparable results as the density matrix renormalization group method for potential energy surfaces along simultaneous dissociation of all C-C bonds.

Keywords

Cite

@article{arxiv.2007.05989,
  title  = {Describing Strong Correlation with Block-Correlated Coupled Cluster Theory},
  author = {Qingchun Wang and Mingzhou Duan and Enhua Xu and Jingxiang Zou and Shuhua Li},
  journal= {arXiv preprint arXiv:2007.05989},
  year   = {2023}
}
R2 v1 2026-06-23T17:03:20.740Z