Materials Data on Sn3Ge by Materials Project
Sn3Ge is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Sn sites. In the first Sn site, Sn is bonded to eight Sn and four equivalent Ge atoms to form distorted SnSn8Ge4 cuboctahedra that share corners with twelve equivalent SnSn8Ge4 cuboctahedra, edges with eight equivalent GeSn12 cuboctahedra, edges with sixteen SnSn8Ge4 cuboctahedra, faces with four equivalent GeSn12 cuboctahedra, and faces with fourteen SnSn8Ge4 cuboctahedra. There are four shorter (3.25 Å) and four longer (3.35 Å) Sn–Sn bond lengths. All Sn–Ge bond lengths are 3.35 Å. In the second Sn site, Sn is bonded to eight equivalent Sn and four equivalent Ge atoms to form SnSn8Ge4 cuboctahedra that share corners with four equivalent SnSn8Ge4 cuboctahedra, corners with eight equivalent GeSn12 cuboctahedra, edges with twenty-four SnSn8Ge4 cuboctahedra, faces with six equivalent GeSn12 cuboctahedra, and faces with twelve SnSn8Ge4 cuboctahedra. All Sn–Ge bond lengths are 3.25 Å. Ge is bonded to twelve Sn atoms to form distorted GeSn12 cuboctahedra that share corners with four equivalent GeSn12 cuboctahedra, corners with eight equivalent SnSn8Ge4 cuboctahedra, edges with eight equivalent GeSn12 cuboctahedra, edges with sixteen equivalent SnSn8Ge4 cuboctahedra, faces with four equivalent GeSn12 cuboctahedra, and faces with fourteen SnSn8Ge4 cuboctahedra.