A new multi-center approach to the exchange-correlation interactions in ab initio tight-binding methods
Abstract
A new approximate method to calculate exchange-correlation contributions in the framework of first-principles tight-binding molecular dynamics methods has been developed. In the proposed scheme on-site (off-site) exchange-correlation matrix elements are expressed as a one-center (two-center) term plus a {\it correction} due to the rest of the atoms. The one-center (two-center) term is evaluated directly, while the {\it correction} is calculated using a variation of the Sankey-Niklewski \cite{Sankey89} approach generalized for arbitrary atomic-like basis sets. The proposed scheme for exchange-correlation part permits the accurate and computationally efficient calculation of corresponding tight-binding matrices and atomic forces for complex systems. We calculate bulk properties of selected transition (W,Pd), noble (Au) or simple (Al) metals, a semiconductor (Si) and the transition metal oxide Ti with the new method to demonstrate its flexibility and good accuracy.
Cite
@article{arxiv.cond-mat/0409509,
title = {A new multi-center approach to the exchange-correlation interactions in ab initio tight-binding methods},
author = {P. Jelinek and H. Wang and J. P. Lewis and O. F. Sankey and J. Ortega},
journal= {arXiv preprint arXiv:cond-mat/0409509},
year = {2009}
}
Comments
17 pages, 5 figures