DOE OSTI2020
Mn6GaGe is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are six inequivalent Mn sites. In the first Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GeMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GeMn12 cuboctahedra, edges with four equivalent GaMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.50–2.67 Å. Both Mn–Ga bond lengths are 2.59 Å. There are one shorter (2.58 Å) and one longer (2.59 Å) Mn–Ge bond lengths. In the second Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GeMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GeMn12 cuboctahedra, edges with four equivalent GaMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.50–2.67 Å. Both Mn–Ga bond lengths are 2.60 Å. Both Mn–Ge bond lengths are 2.59 Å. In the third Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GeMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GeMn12 cuboctahedra, edges with four equivalent GaMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.54 Å) Mn–Mn bond lengths. Both Mn–Ga bond lengths are 2.59 Å. There are one shorter (2.58 Å) and one longer (2.59 Å) Mn–Ge bond lengths. In the fourth Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GaMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GaMn12 cuboctahedra, edges with four equivalent GeMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.47–2.70 Å. There are one shorter (2.58 Å) and one longer (2.59 Å) Mn–Ga bond lengths. Both Mn–Ge bond lengths are 2.60 Å. In the fifth Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GaMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GaMn12 cuboctahedra, edges with four equivalent GeMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are one shorter (2.47 Å) and one longer (2.70 Å) Mn–Mn bond lengths. Both Mn–Ga bond lengths are 2.59 Å. Both Mn–Ge bond lengths are 2.61 Å. In the sixth Mn site, Mn is bonded to eight Mn, two equivalent Ga, and two equivalent Ge atoms to form distorted MnMn8Ga2Ge2 cuboctahedra that share corners with four equivalent GaMn12 cuboctahedra, corners with fourteen MnMn8Ga2Ge2 cuboctahedra, edges with two equivalent GaMn12 cuboctahedra, edges with four equivalent GeMn12 cuboctahedra, edges with twelve MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, and faces with sixteen MnMn8Ga2Ge2 cuboctahedra. There are one shorter (2.58 Å) and one longer (2.59 Å) Mn–Ga bond lengths. Both Mn–Ge bond lengths are 2.60 Å. Ga is bonded to twelve Mn atoms to form GaMn12 cuboctahedra that share corners with six equivalent GaMn12 cuboctahedra, corners with twelve MnMn8Ga2Ge2 cuboctahedra, edges with eighteen MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GaMn12 cuboctahedra, faces with six equivalent GeMn12 cuboctahedra, and faces with twelve MnMn8Ga2Ge2 cuboctahedra. Ge is bonded to twelve Mn atoms to form GeMn12 cuboctahedra that share corners with six equivalent GeMn12 cuboctahedra, corners with twelve MnMn8Ga2Ge2 cuboctahedra, edges with eighteen MnMn8Ga2Ge2 cuboctahedra, faces with two equivalent GeMn12 cuboctahedra, faces with six equivalent GaMn12 cuboctahedra, and faces with twelve MnMn8Ga2Ge2 cuboctahedra.