Flexible Ansatz for N-body Perturbation Theory

Ramón Alain Miranda-Quintana; Taewon D. Kim; Rugwed A. Lokhande; M. Richer; Gabriela Sánchez-Díaz; Pratiksha B. Gaikwad; Paul W. Ayers

arXiv · 2310.03096

Flexible Ansatz for N-body Perturbation Theory

Ramón Alain Miranda-Quintana·Taewon D. Kim·Rugwed A. Lokhande·M. Richer·Gabriela Sánchez-Díaz·Pratiksha B. Gaikwad·Paul W. Ayers

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Abstract

We propose a new Perturbation Theory framework that can be used to help with the projective solution of the Schr\"odinger equation for arbitrary wavefunctions. This Flexible Ansatz for N-body Perturbation Theory (FANPT) is based on our previously proposed Flexible Ansatz for N-body Configuration Interaction (FANCI). We derive recursive FANPT expressions including arbitrary orders in the perturbation hierarchy. We show that the FANPT equations are well-behaved across a wide range of conditions, including static correlation-dominated configurations and highly non-linear wavefunctions.

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Ramón Alain Miranda-Quintana, Taewon D. Kim, Rugwed A. Lokhande, M. Richer, Gabriela Sánchez-Díaz, Pratiksha B. Gaikwad, Paul W. Ayers. 2023-10-04. Flexible Ansatz for N-body Perturbation Theory. https://arxiv.org/abs/2310.03096

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