We investigate the properties of BaNi2As2 using first principles calculations. The band structure has a similar shape to that of the BaFe2As2, and in particular shows a pseudogap between a manifold of six heavy d electron bands and four lighter d bands, i.e. at an electron count of six d electrons per Ni. However, unlike BaFe2As2, where the Fermi energy occurs at the bottom of the pseudogap, the two additional electrons per Ni in the Ni compound place the Fermi energy in the upper manifold. Thus BaNi2As2 has large Fermi surfaces very distinct from BaFe2As2. Results for the phonon spectrum and electron-phonon coupling are consistent with a classification of this material as a conventional phonon mediated superconductor although spin fluctuations and nearness to magnetism may be anticipated based on the value of N(EF).
@article{arxiv.0809.0499,
title = {Density functional study of BaNi$_2$As$_2$: Electronic structure, phonons and electron-phonon superconductivity},
author = {Alaska Subedi and David J. Singh},
journal= {arXiv preprint arXiv:0809.0499},
year = {2008}
}