DOE OSTI2020
Ta2Co3Ga crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ta is bonded in a 12-coordinate geometry to four equivalent Ta, nine equivalent Co, and three equivalent Ga atoms. There are one shorter (2.89 Å) and three longer (2.98 Å) Ta–Ta bond lengths. There are three shorter (2.73 Å) and six longer (2.85 Å) Ta–Co bond lengths. All Ta–Ga bond lengths are 2.87 Å. Co is bonded to six equivalent Ta, four equivalent Co, and two equivalent Ga atoms to form CoTa6Ga2Co4 cuboctahedra that share corners with four equivalent GaTa6Co6 cuboctahedra, corners with fourteen equivalent CoTa6Ga2Co4 cuboctahedra, edges with six equivalent CoTa6Ga2Co4 cuboctahedra, faces with six equivalent GaTa6Co6 cuboctahedra, and faces with twelve equivalent CoTa6Ga2Co4 cuboctahedra. There are two shorter (2.36 Å) and two longer (2.54 Å) Co–Co bond lengths. Both Co–Ga bond lengths are 2.41 Å. Ga is bonded to six equivalent Ta and six equivalent Co atoms to form GaTa6Co6 cuboctahedra that share corners with twelve equivalent CoTa6Ga2Co4 cuboctahedra, edges with six equivalent GaTa6Co6 cuboctahedra, faces with two equivalent GaTa6Co6 cuboctahedra, and faces with eighteen equivalent CoTa6Ga2Co4 cuboctahedra.