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Structural Behavior of Non-Oxide Perovskite Superconductor MgCNi$_{3}$ at Pressures up to 32 GPa

Ravhi S Kumar·A. L. Cornelius·Yongrong Shen·T. Geetha Kumary·J. Janaki·M. C. Valsakumar·Malcolm F. Nicol
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Abstract

We report the pressure dependence of the structural parameters of the non-oxide perovskite superconductor MgCNi$_{3}$ up to 32 GPa using a diamond anvil cell and synchrotron x-rays at room temperature. The structure of the compound remains in the Pm-3m cubic symmetry throughout the pressure range. The bulk modulus $B_{0}=156.9\pm0.2$GPa with $B_{0}^{\prime}=9.8$obtained by fitting the pressure-volume data is in good agreement with theoretical calculations reported earlier. An anomalous shift of the (111) and (200) lines observed above 9 GPa indicates a possible local short range distortion that is consistent with earlier studies.

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Ravhi S Kumar, A. L. Cornelius, Yongrong Shen, T. Geetha Kumary, J. Janaki, M. C. Valsakumar, Malcolm F. Nicol. 2004-10-18. Structural Behavior of Non-Oxide Perovskite Superconductor MgCNi$_{3}$ at Pressures up to 32 GPa. https://doi.org/10.1016/j.physb.2005.03.020

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