Cs3AlTe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to one Te(1), two equivalent Te(3), and three equivalent Te(2) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Al(1), two equivalent Te(1), two equivalent Te(2), and three equivalent Te(3) atoms. In the third Cs site, Cs(3) is bonded in a 5-coordinate geometry to one Te(1), two equivalent Te(2), and two equivalent Te(3) atoms. Al(1) is bonded to one Cs(2), one Te(2), one Te(3), and two equivalent Te(1) atoms to form edge-sharing AlCsTe4 tetrahedra. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded in a 6-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and two equivalent Al(1) atoms. In the second Te site, Te(2) is bonded in a 8-coordinate geometry to two equivalent Cs(2), two equivalent Cs(3), three equivalent Cs(1), and one Al(1) atom. In the third Te site, Te(3) is bonded in a 1-coordinate geometry to two equivalent Cs(1), two equivalent Cs(3), three equivalent Cs(2), and one Al(1) atom.
Cs3AlTe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 6-coordinate geometry to one Te(1), two equivalent Te(3), and three equivalent Te(2) atoms. The Cs(1)-Te(1) bond length is 3.81 Å. There is one shorter (3.85 Å) and one longer (3.91 Å) Cs(1)-Te(3) bond length. There are a spread of Cs(1)-Te(2) bond distances ranging from 3.88-4.40 Å. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Al(1), two equivalent Te(1), two equivalent Te(2), and three equivalent Te(3) atoms. The Cs(2)-Al(1) bond length is 3.95 Å. There is one shorter (3.77 Å) and one longer (3.91 Å) Cs(2)-Te(1) bond length. There is one shorter (3.94 Å) and one longer (4.11 Å) Cs(2)-Te(2) bond length. There are a spread of Cs(2)-Te(3) bond distances ranging from 4.06-4.44 Å. In the third Cs site, Cs(3) is bonded in a 5-coordinate geometry to one Te(1), two equivalent Te(2), and two equivalent Te(3) atoms. The Cs(3)-Te(1) bond length is 4.06 Å. There is one shorter (3.71 Å) and one longer (3.88 Å) Cs(3)-Te(2) bond length. There is one shorter (3.80 Å) and one longer (3.91 Å) Cs(3)-Te(3) bond length. Al(1) is bonded to one Cs(2), one Te(2), one Te(3), and two equivalent Te(1) atoms to form edge-sharing AlCsTe4 tetrahedra. The Al(1)-Te(2) bond length is 2.62 Å. The Al(1)-Te(3) bond length is 2.60 Å. There is one shorter (2.67 Å) and one longer (2.71 Å) Al(1)-Te(1) bond length. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded in a 6-coordinate geometry to one Cs(1), one Cs(3), two equivalent Cs(2), and two equivalent Al(1) atoms. In the second Te site, Te(2) is bonded in a 8-coordinate geometry to two equivalent Cs(2), two equivalent Cs(3), three equivalent Cs(1), and one Al(1) atom. In the third Te site, Te(3) is bonded in a 1-coordinate geometry to two equivalent Cs(1), two equivalent Cs(3), three equivalent Cs(2), and one Al(1) atom.