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Electronic structure, magnetism and superconductivity of MgCNi$_{3}$

S. B. Dugdale·T. Jarlborg
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Abstract

The electronic structure of the newly discovered superconducting perovskite MgCNi$_3$ is calculated using the LMTO and KKR methods. The states near the Fermi energy are found to be dominated by Ni-d. The Stoner factor is low while the electron-phonon coupling constant is estimated to be about 0.7, which suggests that the material is a conventional type of superconductor where T$_C$ is not affected by magnetic interactions. However, the proximity of the Fermi energy to a large peak in the density of states in conjunction with the reported non-stoichiometry of the compound, has consequences for the stability of the results.

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S. B. Dugdale, T. Jarlborg. 2001-05-17. Electronic structure, magnetism and superconductivity of MgCNi$_{3}$. https://doi.org/10.1103/physrevb.64.100508

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