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Electronic structures of antiperovskite superconductors: MgXNi$_3$ (X=B,C,N)

J. H. Shim·B. I. Min
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Abstract

We have investigated electronic structures of a newly discovered antiperovskite superconductor MgCNi$_3$ and related compounds MgBNi$_3$ and MgNNi$_3$. In MgCNi$_3$, a peak of very narrow and high density of states is located just below $\rm E_F$, which corresponds to the $π^*$ antibonding state of Ni-3d and C-$2p$ but with the predominant Ni-3d character. The prominent nesting feature is observed in the $Γ$-centered electron Fermi surface of an octahedron-cage-like shape that originates from the 19th band. The estimated superconducting parameters based on the simple rigid-ion approximation are in reasonable agreement with experiment, suggesting that the superconductivity in MgCNi$_3$ is described well by the conventional phonon mechanism.

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J. H. Shim, B. I. Min. 2001-05-22. Electronic structures of antiperovskite superconductors: MgXNi$_3$ (X=B,C,N). https://doi.org/10.1103/physrevb.64.180510

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