The beryllium dimer and trimer are, despite their small number of electrons, excellent systems for assessing electronic-structure computational methods. With reference data provided by multi-reference averaged coupled-pair functional calculations, we assess several variants of range-separated density-functional theory, combining long-range second-order perturbation theory or coupled-cluster theory with a short-range density functional. The results show that i) long-range second-order perturbation theory is not sufficient, ii) long-range coupled-cluster theory gives reasonably accurate potential energy curves, but iii) provided a relatively large value of μ=1 bohr−1 for the range-separationparameter is used. The article is dedicated to the memory of J\'anos G. \'Angy\'an.
@article{arxiv.1809.08814,
title = {Range-separated density-functional theory applied to the beryllium dimer and trimer},
author = {Peter Reinhardt and Julien Toulouse and Andreas Savin},
journal= {arXiv preprint arXiv:1809.08814},
year = {2018}
}
Comments
Theoretical Chemistry Accounts: Theory, Computation, and Modeling, Springer Verlag, In press