Yb(YSe2)2 crystallizes in the monoclinic P2/m space group. Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YbSe6 octahedra that share corners with six equivalent Y(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with four equivalent Y(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YSe6 octahedra that share corners with six equivalent Yb(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with four equivalent Y(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Y site, Y(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form YSe6 octahedra that share edges with two equivalent Y(2)Se6 octahedra, edges with four equivalent Yb(1)Se6 octahedra, and edges with four equivalent Y(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of edge and corner-sharing SeYb2Y3 square pyramids. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Y(1), and two equivalent Y(2) atoms.
Yb(YSe2)2 crystallizes in the monoclinic P2/m space group. Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YbSe6 octahedra that share corners with six equivalent Y(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with four equivalent Y(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. Both Yb(1)-Se(2) bond lengths are 2.90 Å. All Yb(1)-Se(1) bond lengths are 2.95 Å. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YSe6 octahedra that share corners with six equivalent Yb(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with four equivalent Y(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. Both Y(1)-Se(2) bond lengths are 2.83 Å. All Y(1)-Se(1) bond lengths are 2.90 Å. In the second Y site, Y(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form YSe6 octahedra that share edges with two equivalent Y(2)Se6 octahedra, edges with four equivalent Yb(1)Se6 octahedra, and edges with four equivalent Y(1)Se6 octahedra. Both Y(2)-Se(1) bond lengths are 2.87 Å. All Y(2)-Se(2) bond lengths are 2.86 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of edge and corner-sharing SeYb2Y3 square pyramids. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Y(1), and two equivalent Y(2) atoms.