2022/03/05 by Paul A. Johnson, Johnson, Paul A., Paul W. Ayers +7 · 3 citations
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Advanced Chemical Physics Studies #Chemical Physics (physics.chem-ph) #Electron Spin Resonance Studies #FOS: Physical sciences #Spectroscopy and Quantum Chemical Studies #physics.chem-ph
paper · pdf · doi:10.48550/arxiv.2203.02624
arxiv created 2022/03/05 · openalex publication_date 2022/03/05 · arxiv updated 2022/03/08 · openalex created_date 2022/04/03 · openalex updated_date 2026/07/28
We develop a bivariational principle for an antisymmetric product of nonorthogonal geminals. Special cases reduce to the antisymmetric product of strongly-orthogonal geminals (APSG), the generalized valence bond-perfect pairing (GVB-PP), and the antisymmetrized geminal power (AGP) wavefunctions. The presented method employs wavefunctions of the same type as Richardson-Gaudin (RG) states, but which are not eigenvectors of a model Hamiltonian which would allow for more freedom in the mean-field. The general idea is to work with the same state in a primal picture in terms of pairs, and in a dual picture in terms of pair-holes. This leads to an asymmetric energy expression which may be optimized bivariationally, and is strictly variational when the two representations are consistent. The general approach may be useful in other contexts, such as for computationally feasible variational coupled-cluster methods.