English

Flexible Ansatz for N-body Perturbation Theory

Chemical Physics 2023-10-06 v1

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.

Keywords

Cite

@article{arxiv.2310.03096,
  title  = {Flexible Ansatz for N-body Perturbation Theory},
  author = {Ramón Alain Miranda-Quintana and Taewon D. Kim and Rugwed A. Lokhande and M. Richer and Gabriela Sánchez-Díaz and Pratiksha B. Gaikwad and Paul W. Ayers},
  journal= {arXiv preprint arXiv:2310.03096},
  year   = {2023}
}