We report calculations of the electronic structure of CaB6 using the weighted density approximation (WDA) to density functional theory. We find a semiconducting band structure with a sizable gap, in contrast to local density approximation (LDA) results, but in accord with recent experimental data. In particular, we find an X-point band gap of 0.8 eV. The WDA correction of the LDA error in describing the electronic structure of CaB6 is discussed in terms of the orbital character of the bands and the better cancelation of self-interactions within the WDA.
@article{arxiv.cond-mat/0401246,
title = {Electronic Structure of Calcium Hexaboride within the Weighted Density Approximation},
author = {Z. Wu and D. J. Singh and R. E. Cohen},
journal= {arXiv preprint arXiv:cond-mat/0401246},
year = {2009}
}