Perturbation-Adapted Perturbation Theory
Quantum Physics
2021-12-09 v3 Strongly Correlated Electrons
Chemical Physics
Abstract
A new general approach is introduced for definining an optimum zero-order Hamiltonian for Rayleigh-Schr\"odinger perturbation theory. Instead of taking the operator directly from a model problem, it is constructed to be a best fit to the exact Hamiltonian within any desired functional form. When applied to many-body perturbation theory for electrons, strongly improved convergence is observed in cases where the conventional Fock hamiltonian leads to divergence or slow convergence.
Cite
@article{arxiv.2111.09271,
title = {Perturbation-Adapted Perturbation Theory},
author = {Peter J. Knowles},
journal= {arXiv preprint arXiv:2111.09271},
year = {2021}
}
Comments
4 pages, 2 figures, minor revisions