Yb2Se3 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles range from 2-17°. In the second Yb site, Yb(2) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a see-saw-like geometry to two equivalent Yb(1) and two equivalent Yb(2) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Yb(1), two equivalent Yb(2), and one Se(2) atom.
Yb2Se3 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles range from 2-17°. Both Yb(1)-Se(2) bond lengths are 3.00 Å. There are two shorter (2.89 Å) and two longer (2.91 Å) Yb(1)-Se(1) bond lengths. In the second Yb site, Yb(2) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing YbSe6 octahedra. The corner-sharing octahedral tilt angles are 2°. Both Yb(2)-Se(2) bond lengths are 2.98 Å. There are two shorter (2.91 Å) and two longer (3.00 Å) Yb(2)-Se(1) bond lengths. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a see-saw-like geometry to two equivalent Yb(1) and two equivalent Yb(2) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Yb(1), two equivalent Yb(2), and one Se(2) atom. The Se(2)-Se(2) bond length is 2.43 Å.