Sn3.0Cu is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded to four equivalent Sn(2) and eight equivalent Sn(1) atoms to form CuSn12 cuboctahedra that share corners with four equivalent Cu(1)Sn12 cuboctahedra, corners with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, edges with eight equivalent Cu(1)Sn12 cuboctahedra, edges with sixteen equivalent Sn(1)Cu4Sn8 cuboctahedra, faces with four equivalent Cu(1)Sn12 cuboctahedra, faces with six equivalent Sn(2)Cu4Sn8 cuboctahedra, and faces with eight equivalent Sn(1)Cu4Sn8 cuboctahedra. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to four equivalent Cu(1), four equivalent Sn(1), and four equivalent Sn(2) atoms to form SnCu4Sn8 cuboctahedra that share corners with twelve equivalent Sn(1)Cu4Sn8 cuboctahedra, edges with eight equivalent Cu(1)Sn12 cuboctahedra, edges with eight equivalent Sn(1)Cu4Sn8 cuboctahedra, edges with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, faces with four equivalent Cu(1)Sn12 cuboctahedra, faces with four equivalent Sn(2)Cu4Sn8 cuboctahedra, and faces with ten equivalent Sn(1)Cu4Sn8 cuboctahedra. In the second Sn site, Sn(2) is bonded to four equivalent Cu(1) and eight equivalent Sn(1) atoms to form SnCu4Sn8 cuboctahedra that share corners with four equivalent Sn(2)Cu4Sn8 cuboctahedra, corners with eight equivalent Cu(1)Sn12 cuboctahedra, edges with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, edges with sixteen equivalent Sn(1)Cu4Sn8 cuboctahedra, faces with four equivalent Sn(2)Cu4Sn8 cuboctahedra, faces with six equivalent Cu(1)Sn12 cuboctahedra, and faces with eight equivalent Sn(1)Cu4Sn8 cuboctahedra.
Sn3.0Cu is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded to four equivalent Sn(2) and eight equivalent Sn(1) atoms to form CuSn12 cuboctahedra that share corners with four equivalent Cu(1)Sn12 cuboctahedra, corners with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, edges with eight equivalent Cu(1)Sn12 cuboctahedra, edges with sixteen equivalent Sn(1)Cu4Sn8 cuboctahedra, faces with four equivalent Cu(1)Sn12 cuboctahedra, faces with six equivalent Sn(2)Cu4Sn8 cuboctahedra, and faces with eight equivalent Sn(1)Cu4Sn8 cuboctahedra. All Cu(1)-Sn(2) bond lengths are 3.17 Å. All Cu(1)-Sn(1) bond lengths are 3.31 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to four equivalent Cu(1), four equivalent Sn(1), and four equivalent Sn(2) atoms to form SnCu4Sn8 cuboctahedra that share corners with twelve equivalent Sn(1)Cu4Sn8 cuboctahedra, edges with eight equivalent Cu(1)Sn12 cuboctahedra, edges with eight equivalent Sn(1)Cu4Sn8 cuboctahedra, edges with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, faces with four equivalent Cu(1)Sn12 cuboctahedra, faces with four equivalent Sn(2)Cu4Sn8 cuboctahedra, and faces with ten equivalent Sn(1)Cu4Sn8 cuboctahedra. All Sn(1)-Sn(1) bond lengths are 3.17 Å. All Sn(1)-Sn(2) bond lengths are 3.31 Å. In the second Sn site, Sn(2) is bonded to four equivalent Cu(1) and eight equivalent Sn(1) atoms to form SnCu4Sn8 cuboctahedra that share corners with four equivalent Sn(2)Cu4Sn8 cuboctahedra, corners with eight equivalent Cu(1)Sn12 cuboctahedra, edges with eight equivalent Sn(2)Cu4Sn8 cuboctahedra, edges with sixteen equivalent Sn(1)Cu4Sn8 cuboctahedra, faces with four equivalent Sn(2)Cu4Sn8 cuboctahedra, faces with six equivalent Cu(1)Sn12 cuboctahedra, and faces with eight equivalent Sn(1)Cu4Sn8 cuboctahedra.