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Phonon spectrum and soft-mode behavior of MgCNi_3

R. Heid·B. Renker·H. Schober·P. Adelmann·D. Ernst·K. -P. Bohnen
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Abstract

Temperature dependent inelastic neutron-scattering measurements of the generalized phonon density-of-states for superconducting MgCNi_3, T_c=8 K, give evidence for a soft-mode behavior of low-frequency Ni phonon modes. Results are compared with ab initio density functional calculations which suggest an incipient lattice instability of the stoichiometric compound with respect to Ni vibrations orthogonal to the Ni-C bond direction.

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R. Heid, B. Renker, H. Schober, P. Adelmann, D. Ernst, K. -P. Bohnen. 2003-10-24. Phonon spectrum and soft-mode behavior of MgCNi_3. https://doi.org/10.1103/physrevb.69.092511

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