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arXiv · 0708.0179

Crystal Structure and Physical Properties of Mg6Cu16Si7-type M6Ni16Si7, for M = Mg, Sc, Ti, Nb, and Ta

K. L. Holman·E. Morosan·P. A. Casey·Lu Li·N. P. Ong·T. Klimczuk·C. Felser·R. J. Cava
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Abstract

Five compounds were investigated for magnetic character and superconductivity, all with non-magnetic nickel and band structures containing flat bands and steep bands. The syntheses and crystal structures, refined by powder X-ray diffraction, are reported for M6Ni16Si7, where M = Mg, Sc, Ti, Nb, and Ta. All compounds form in the Mg6Cu16Si7 structure type. Resistance measurements are also reported on M6Ni16Si7 (M = Mg, Sc, Ti, and Nb) down to 0.3 K, with all four showing metallic conductivity. No superconductivity is observed. Magnetization measurements for all compounds reveal essentially temperature independent paramagnetism, with a tendency toward more enhanced low temperature paramagnetism for the cases of Mg6Ni16Si7 and Sc6Ni16Si7.

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K. L. Holman, E. Morosan, P. A. Casey, Lu Li, N. P. Ong, T. Klimczuk, C. Felser, R. J. Cava. 2007-08-15. Crystal Structure and Physical Properties of Mg6Cu16Si7-type M6Ni16Si7, for M = Mg, Sc, Ti, Nb, and Ta. https://arxiv.org/abs/0708.0179

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