CeCrSe3 crystallizes in the orthorhombic Pnma space group. Ce(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(3), and four equivalent Se(2) atoms. Cr(1) is bonded to one Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form edge-sharing CrSe6 octahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(1) and three equivalent Cr(1) atoms to form distorted SeCe2Cr3 trigonal bipyramids that share corners with three equivalent Se(2)Ce4Cr square pyramids, corners with four equivalent Se(1)Ce2Cr3 trigonal bipyramids, edges with four equivalent Se(2)Ce4Cr square pyramids, and edges with two equivalent Se(1)Ce2Cr3 trigonal bipyramids. In the second Se site, Se(2) is bonded to four equivalent Ce(1) and one Cr(1) atom to form distorted SeCe4Cr square pyramids that share corners with four equivalent Se(2)Ce4Cr square pyramids, corners with three equivalent Se(1)Ce2Cr3 trigonal bipyramids, edges with four equivalent Se(2)Ce4Cr square pyramids, and edges with four equivalent Se(1)Ce2Cr3 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent Ce(1) and two equivalent Cr(1) atoms.
CeCrSe3 crystallizes in the orthorhombic Pnma space group. Ce(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(3), and four equivalent Se(2) atoms. There is one shorter (3.14 Å) and one longer (3.36 Å) Ce(1)-Se(1) bond length. There are two shorter (3.07 Å) and one longer (3.19 Å) Ce(1)-Se(3) bond length. All Ce(1)-Se(2) bond lengths are 3.10 Å. Cr(1) is bonded to one Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form edge-sharing CrSe6 octahedra. The Cr(1)-Se(2) bond length is 2.51 Å. Both Cr(1)-Se(3) bond lengths are 2.59 Å. There is one shorter (2.51 Å) and two longer (2.56 Å) Cr(1)-Se(1) bond lengths. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ce(1) and three equivalent Cr(1) atoms to form distorted SeCe2Cr3 trigonal bipyramids that share corners with three equivalent Se(2)Ce4Cr square pyramids, corners with four equivalent Se(1)Ce2Cr3 trigonal bipyramids, edges with four equivalent Se(2)Ce4Cr square pyramids, and edges with two equivalent Se(1)Ce2Cr3 trigonal bipyramids. In the second Se site, Se(2) is bonded to four equivalent Ce(1) and one Cr(1) atom to form distorted SeCe4Cr square pyramids that share corners with four equivalent Se(2)Ce4Cr square pyramids, corners with three equivalent Se(1)Ce2Cr3 trigonal bipyramids, edges with four equivalent Se(2)Ce4Cr square pyramids, and edges with four equivalent Se(1)Ce2Cr3 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent Ce(1) and two equivalent Cr(1) atoms.