Geminal-Based Configuration Interaction

Thomas M. Henderson; Gustavo E. Scuseria

doi:10.1063/1.5116715

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arXiv · 1906.11361

Geminal-Based Configuration Interaction

Thomas M. Henderson·Gustavo E. Scuseria

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Abstract

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.

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Thomas M. Henderson, Gustavo E. Scuseria. 2019-06-26. Geminal-Based Configuration Interaction. https://doi.org/10.1063/1.5116715

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