Yb(CuSe)3 crystallizes in the trigonal R-3 space group. Yb(1) is bonded to six equivalent Se(1) atoms to form YbSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Yb(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Yb(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Yb(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-55°. Se(1) is bonded in a 6-coordinate geometry to two equivalent Yb(1) and four equivalent Cu(1) atoms.
Yb(CuSe)3 crystallizes in the trigonal R-3 space group. Yb(1) is bonded to six equivalent Se(1) atoms to form YbSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Yb(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. All Yb(1)-Se(1) bond lengths are 2.91 Å. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Yb(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Yb(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-55°. There are a spread of Cu(1)-Se(1) bond distances ranging from 2.43-2.51 Å. Se(1) is bonded in a 6-coordinate geometry to two equivalent Yb(1) and four equivalent Cu(1) atoms.