Sc(CuSe)3 crystallizes in the trigonal R-3 space group. Sc(1) is bonded to six equivalent Se(1) atoms to form ScSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Sc(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Sc(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Sc(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-60°. Se(1) is bonded to two equivalent Sc(1) and four equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing SeSc2Cu4 octahedra. The corner-sharing octahedral tilt angles range from 2-95°.
Sc(CuSe)3 crystallizes in the trigonal R-3 space group. Sc(1) is bonded to six equivalent Se(1) atoms to form ScSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Sc(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. All Sc(1)-Se(1) bond lengths are 2.73 Å. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Sc(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Sc(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-60°. There are a spread of Cu(1)-Se(1) bond distances ranging from 2.40-2.50 Å. Se(1) is bonded to two equivalent Sc(1) and four equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing SeSc2Cu4 octahedra. The corner-sharing octahedral tilt angles range from 2-95°.