TbCrSe3 crystallizes in the orthorhombic Pnma space group. Tb(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and four equivalent Se(3) atoms. Cr(1) is bonded to one Se(3), two equivalent Se(2), 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 in a 5-coordinate geometry to two equivalent Tb(1) and three equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to three equivalent Tb(1) and two equivalent Cr(1) atoms. In the third Se site, Se(3) is bonded to four equivalent Tb(1) and one Cr(1) atom to form a mixture of distorted corner and edge-sharing SeTb4Cr square pyramids.
TbCrSe3 crystallizes in the orthorhombic Pnma space group. Tb(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and four equivalent Se(3) atoms. There is one shorter (3.00 Å) and one longer (3.49 Å) Tb(1)-Se(1) bond length. There are two shorter (2.99 Å) and one longer (3.07 Å) Tb(1)-Se(2) bond length. All Tb(1)-Se(3) bond lengths are 3.06 Å. Cr(1) is bonded to one Se(3), two equivalent Se(2), and three equivalent Se(1) atoms to form edge-sharing CrSe6 octahedra. The Cr(1)-Se(3) bond length is 2.50 Å. Both Cr(1)-Se(2) bond lengths are 2.58 Å. There is one shorter (2.49 Å) and two longer (2.54 Å) Cr(1)-Se(1) bond lengths. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Tb(1) and three equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to three equivalent Tb(1) and two equivalent Cr(1) atoms. In the third Se site, Se(3) is bonded to four equivalent Tb(1) and one Cr(1) atom to form a mixture of distorted corner and edge-sharing SeTb4Cr square pyramids.