Materials Data on ScCuSi by Materials Project
ScCuSi crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Sc3+ is bonded to five Si4- atoms to form ScSi5 square pyramids that share corners with ten equivalent ScSi5 square pyramids, corners with six equivalent CuSi4 tetrahedra, edges with six equivalent ScSi5 square pyramids, and edges with six equivalent CuSi4 tetrahedra. There are four shorter (2.74 Å) and one longer (2.76 Å) Sc–Si bond lengths. Cu1+ is bonded to four Si4- atoms to form CuSi4 tetrahedra that share corners with six equivalent ScSi5 square pyramids, corners with ten equivalent CuSi4 tetrahedra, edges with six equivalent ScSi5 square pyramids, and edges with two equivalent CuSi4 tetrahedra. There are two shorter (2.48 Å) and two longer (2.51 Å) Cu–Si bond lengths. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to three equivalent Sc3+ and six equivalent Cu1+ atoms. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to six equivalent Sc3+ and three equivalent Cu1+ atoms.