LaSbSe3 crystallizes in the orthorhombic Pnma space group. La(1) is bonded in a 8-coordinate geometry to two equivalent Se(3), three equivalent Se(1), and three equivalent Se(2) atoms. Sb(1) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted edge-sharing SbSe5 square pyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to three equivalent La(1) and one Sb(1) atom. In the second Se site, Se(2) is bonded to three equivalent La(1) and two equivalent Sb(1) atoms to form edge-sharing SeLa3Sb2 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent La(1) and two equivalent Sb(1) atoms.
LaSbSe3 crystallizes in the orthorhombic Pnma space group. La(1) is bonded in a 8-coordinate geometry to two equivalent Se(3), three equivalent Se(1), and three equivalent Se(2) atoms. Both La(1)-Se(3) bond lengths are 3.17 Å. There are two shorter (3.06 Å) and one longer (3.58 Å) La(1)-Se(1) bond length. There are two shorter (3.07 Å) and one longer (3.12 Å) La(1)-Se(2) bond length. Sb(1) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted edge-sharing SbSe5 square pyramids. The Sb(1)-Se(1) bond length is 2.62 Å. Both Sb(1)-Se(2) bond lengths are 2.97 Å. Both Sb(1)-Se(3) bond lengths are 2.86 Å. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to three equivalent La(1) and one Sb(1) atom. In the second Se site, Se(2) is bonded to three equivalent La(1) and two equivalent Sb(1) atoms to form edge-sharing SeLa3Sb2 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent La(1) and two equivalent Sb(1) atoms.