2019/06/30 by Thomas M. Henderson, Gustavo E. Scuseria
Physics and Astronomy · #physics.chem-ph #cond-mat.str-el
paper · pdf · doi:10.1063/1.5116715
published as J. Chem. Phys. 151, 051101 (2019) · Revised manuscript
arxiv created 2019/07/16 · arxiv updated 2020/05/14
The antisymmetrized geminal power (AGP) wave function has a long history and considerable conceptual appeal, but in many situations its accuracy is wanting. Here, we consider a form of configuration interaction (CI) based upon the AGP wave function and taking advantage of its killing operators to construct an excitation manifold. Our geminal CI reduces to standard single-determinant--based CI in the limit in which AGP reduces to a single determinant. It substantially improves upon AGP in the reduced BCS Hamiltonian, which serves as a prototype for the kinds of strong pairing correlations relevant in Bardeen-Cooper-Schrieffer--style superconductivity. Moreover, our geminal CI naturally generalizes to add correlation to more general geminal-based wave functions than AGP.