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DOE OSTI · 1720087

Materials Data on LaMnCuGe2 by Materials Project

Abstract

LaMnCuGe2 crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. La is bonded in a 8-coordinate geometry to four equivalent Mn, four equivalent Cu, and eight equivalent Ge atoms. All La–Mn bond lengths are 3.39 Å. All La–Cu bond lengths are 3.39 Å. All La–Ge bond lengths are 3.26 Å. Mn is bonded to four equivalent La, four equivalent Cu, and four equivalent Ge atoms to form distorted MnLa4Cu4Ge4 tetrahedra that share corners with four equivalent CuLa4Mn4Ge4 cuboctahedra, corners with twelve equivalent MnLa4Cu4Ge4 tetrahedra, edges with two equivalent CuLa4Mn4Ge4 cuboctahedra, faces with four equivalent CuLa4Mn4Ge4 cuboctahedra, and faces with four equivalent MnLa4Cu4Ge4 tetrahedra. All Mn–Cu bond lengths are 2.98 Å. All Mn–Ge bond lengths are 2.50 Å. Cu is bonded to four equivalent La, four equivalent Mn, and four equivalent Ge atoms to form distorted CuLa4Mn4Ge4 cuboctahedra that share corners with twelve equivalent CuLa4Mn4Ge4 cuboctahedra, corners with four equivalent MnLa4Cu4Ge4 tetrahedra, edges with two equivalent MnLa4Cu4Ge4 tetrahedra, faces with four equivalent CuLa4Mn4Ge4 cuboctahedra, and faces with four equivalent MnLa4Cu4Ge4 tetrahedra. All Cu–Ge bond lengths are 2.50 Å. Ge is bonded in a 9-coordinate geometry to four equivalent La, two equivalent Mn, two equivalent Cu, and one Ge atom. The Ge–Ge bond length is 2.61 Å.

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2020-05-02. Materials Data on LaMnCuGe2 by Materials Project. https://doi.org/10.17188/1720087

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36 MATERIALS SCIENCE↗