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Carbon Concentration Dependence of the Superconducting Transition Temperature and Structure of MgCxNi3

T. G. Amos·Q. Huang·J. W. Lynn·T. He·R. J. Cava
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Abstract

The crystal structure of the superconductor MgCxNi3 is reported as a function of carbon concentration determined by powder neutron diffraction. The single-phase perovskite structure was found in only a narrow range of carbon content, 0.88 < x < 1.0. The superconducting transition temperature was found to decrease systematically with decreasing carbon concentration. The introduction of carbon vacancies has a significant effect on the positions of the Ni atoms. No evidence for long range magnetic ordering was seen by neutron diffraction for carbon stoichiometries within the perovskite phase stability range.

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T. G. Amos, Q. Huang, J. W. Lynn, T. He, R. J. Cava. 2001-10-29. Carbon Concentration Dependence of the Superconducting Transition Temperature and Structure of MgCxNi3. https://doi.org/10.1016/s0038-1098(01)00470-7

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