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DOE OSTI · 1839697

A Noncentrosymmetric Polymorph of LuRuGe

Bao, Jin-Ke·Bugaris, Daniel E.·Zheng, Huihuo·Chung, Duck Young·Kanatzidis, Mercouri G.
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Abstract

In this work, we report a new polymorph of LuRuGe, obtained in indium flux. This phase exhibits the noncentrosymmetric ZrNiAl-type structure with the space group $Ρ\bar 62m$ as determined by single-crystal X-ray diffraction. This polymorph can convert into another centrosymmetric polymorph (TiNiSi-type structure, space group Pnma ) at high temperatures. In this work, we performed electrical transport, magnetization, and specific heat measurements on this new phase. It shows metallic behavior with a Hall sign change from negative at 2 K to positive at 125 K. LuRuGe exhibits Pauli paramagnetism as the ground state with no local magnetic moments from either the Ru or Lu site. The Debye temperature Θ = 348 K and electronic coefficient γ e = 3.6 mJ K –2 mol –1 are extracted from the low-temperature specific heat data in LuRuGe. We also carried out first-principles density functional theory calculations to map out the electronic band structure and density of states. There are several electronic bands crossing the Fermi level, supporting a multiband scenario consistent with the Hall sign change. The density of states around the Fermi level is mainly from Ru 4d and Ge 4p electrons, indicating a strong hybridization between those atomic orbitals.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCrystal structureCrystalsDiffractionFluxesPhase transitions

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Bao, Jin-Ke, Bugaris, Daniel E., Zheng, Huihuo, Chung, Duck Young, Kanatzidis, Mercouri G.. 2021-05-17. A Noncentrosymmetric Polymorph of LuRuGe. https://doi.org/10.1021/acs.inorgchem.1c00320

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