DOE OSTI2020
Au5Sn crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are ten inequivalent Au+0.40- sites. In the first Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.96–3.02 Å. All Au–Sn bond lengths are 3.00 Å. In the second Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the third Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are one shorter (2.96 Å) and two longer (3.02 Å) Au–Au bond lengths. Both Au–Sn bond lengths are 3.00 Å. In the fourth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are three shorter (3.01 Å) and two longer (3.02 Å) Au–Au bond lengths. All Au–Sn bond lengths are 3.00 Å. In the fifth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. Both Au–Au bond lengths are 2.96 Å. All Au–Sn bond lengths are 3.00 Å. In the sixth Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the seventh Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.96–3.02 Å. All Au–Sn bond lengths are 3.00 Å. In the eighth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are two shorter (2.96 Å) and one longer (3.02 Å) Au–Au bond lengths. All Au–Sn bond lengths are 3.00 Å. In the ninth Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the tenth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. The Au–Au bond length is 2.96 Å. All Au–Sn bond lengths are 3.00 Å. Sn2+ is bonded to twelve Au+0.40- atoms to form SnAu12 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with six equivalent SnAu12 cuboctahedra, edges with twelve AuSn2Au10 cuboctahedra, and faces with twenty AuSn3Au9 cuboctahedra.