Explicitly Correlated Gaussian Basis Approach to Periodic Systems
Abstract
Closed-form expressions for all matrix elements required for variational calculation of the electronic structure of periodic solids have been derived using a basis of explicitly correlated Gaussians (ECGs). Periodic basis functions are constructed by summing shifted correlated Gaussians over all composite lattice translations, where a generalized unfolding theorem reduces the resulting double lattice sum to a single sum through a unified computational framework for overlap, kinetic energy, and Coulomb potential operators. The formalism has been validated through application to an infinite one-dimensional hydrogen chain, where the ground-state energy per atom computed in the thermodynamic limit is shown to agree with finite-chain results extrapolated by other many-body methods.
Keywords
Cite
@article{arxiv.2605.12781,
title = {Explicitly Correlated Gaussian Basis Approach to Periodic Systems},
author = {Kalman Varga},
journal= {arXiv preprint arXiv:2605.12781},
year = {2026}
}