English

False Prediction of Fundamental Properties of Metals by Hybrid Functionals

Materials Science 2015-04-24 v1

Abstract

The repercussions of an inaccurate account of electronic states near the Fermi level EF by hybrid functionals in predicting several important metallic properties are investigated. The diffculties in- clude a vanishing or severely suppressed density of states (DOS) at EF, significantly widened valence bandwidth, greatly enhanced electron-phonon (el-ph) deformation potentials, and an overestimate of magnetic moment in transition metals. The erroneously enhanced el-ph coupling calculated by hybrid functionals may lead to a false prediction of lattice instability. The main culprit of the problem comes from the simplistic treatment of the exchange functional rooted in the original Fock exchange energy. The use of a short-ranged Coulomb interaction alleviates some of the drawbacks but the fundamental issues remain unchanged.

Keywords

Cite

@article{arxiv.1504.06259,
  title  = {False Prediction of Fundamental Properties of Metals by Hybrid Functionals},
  author = {Weiwei Gao and Tesfaye A. Abtew and Tianyi Cai and Y. Y. Sun and S. B. Zhang and Peihong Zhang},
  journal= {arXiv preprint arXiv:1504.06259},
  year   = {2015}
}