Exact Conditions for Ensemble Density Functional Theory
Strongly Correlated Electrons
2023-07-04 v1 Chemical Physics
Abstract
Ensemble density functional theory (EDFT) is a promising alternative to time-dependent density functional theory for computing electronic excitation energies. Using coordinate scaling, we prove several fundamental exact conditions in EDFT and illustrate them on the exact singlet bi-ensemble of the Hubbard dimer. Several approximations violate these conditions, and some ground-state conditions from quantum chemistry do not generalize to EDFT. The strong-correlation limit is derived for the dimer, revealing weight-dependent derivative discontinuities in EDFT.
Cite
@article{arxiv.2307.00187,
title = {Exact Conditions for Ensemble Density Functional Theory},
author = {Thais R. Scott and John Kozlowski and Steven Crisostomo and Aurora Pribram-Jones and Kieron Burke},
journal= {arXiv preprint arXiv:2307.00187},
year = {2023}
}
Comments
6 pages 5 figures