Cd4TeSe3 is Lavarevi\'{c}ite-like structured and crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one Te(1), one Se(2), and two equivalent Se(1) atoms to form CdTeSe3 tetrahedra that share corners with four equivalent Cd(2)Se4 tetrahedra, corners with four equivalent Cd(3)Te2Se2 tetrahedra, and corners with four equivalent Cd(1)TeSe3 tetrahedra. In the second Cd site, Cd(2) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form CdSe4 tetrahedra that share corners with two equivalent Cd(2)Se4 tetrahedra, corners with two equivalent Cd(3)Te2Se2 tetrahedra, and corners with eight equivalent Cd(1)TeSe3 tetrahedra. In the third Cd site, Cd(3) is bonded to two equivalent Te(1) and two equivalent Se(1) atoms to form CdTe2Se2 tetrahedra that share corners with two equivalent Cd(2)Se4 tetrahedra, corners with two equivalent Cd(3)Te2Se2 tetrahedra, and corners with eight equivalent Cd(1)TeSe3 tetrahedra. Te(1) is bonded to two equivalent Cd(1) and two equivalent Cd(3) atoms to form TeCd4 tetrahedra that share corners with two equivalent Te(1)Cd4 tetrahedra, corners with two equivalent Se(2)Cd4 tetrahedra, and corners with eight equivalent Se(1)Cd4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cd(2), one Cd(3), and two equivalent Cd(1) atoms to form SeCd4 tetrahedra that share corners with four equivalent Te(1)Cd4 tetrahedra, corners with four equivalent Se(1)Cd4 tetrahedra, and corners with four equivalent Se(2)Cd4 tetrahedra. In the second Se site, Se(2) is bonded to two equivalent Cd(1) and two equivalent Cd(2) atoms to form SeCd4 tetrahedra that share corners with two equivalent Te(1)Cd4 tetrahedra, corners with two equivalent Se(2)Cd4 tetrahedra, and corners with eight equivalent Se(1)Cd4 tetrahedra.
Cd4TeSe3 is Lavarevi\'{c}ite-like structured and crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one Te(1), one Se(2), and two equivalent Se(1) atoms to form CdTeSe3 tetrahedra that share corners with four equivalent Cd(2)Se4 tetrahedra, corners with four equivalent Cd(3)Te2Se2 tetrahedra, and corners with four equivalent Cd(1)TeSe3 tetrahedra. The Cd(1)-Te(1) bond length is 2.84 Å. The Cd(1)-Se(2) bond length is 2.69 Å. Both Cd(1)-Se(1) bond lengths are 2.70 Å. In the second Cd site, Cd(2) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form CdSe4 tetrahedra that share corners with two equivalent Cd(2)Se4 tetrahedra, corners with two equivalent Cd(3)Te2Se2 tetrahedra, and corners with eight equivalent Cd(1)TeSe3 tetrahedra. Both Cd(2)-Se(1) bond lengths are 2.70 Å. Both Cd(2)-Se(2) bond lengths are 2.71 Å. In the third Cd site, Cd(3) is bonded to two equivalent Te(1) and two equivalent Se(1) atoms to form CdTe2Se2 tetrahedra that share corners with two equivalent Cd(2)Se4 tetrahedra, corners with two equivalent Cd(3)Te2Se2 tetrahedra, and corners with eight equivalent Cd(1)TeSe3 tetrahedra. Both Cd(3)-Te(1) bond lengths are 2.82 Å. Both Cd(3)-Se(1) bond lengths are 2.71 Å. Te(1) is bonded to two equivalent Cd(1) and two equivalent Cd(3) atoms to form TeCd4 tetrahedra that share corners with two equivalent Te(1)Cd4 tetrahedra, corners with two equivalent Se(2)Cd4 tetrahedra, and corners with eight equivalent Se(1)Cd4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cd(2), one Cd(3), and two equivalent Cd(1) atoms to form SeCd4 tetrahedra that share corners with four equivalent Te(1)Cd4 tetrahedra, corners with four equivalent Se(1)Cd4 tetrahedra, and corners with four equivalent Se(2)Cd4 tetrahedra. In the second Se site, Se(2) is bonded to two equivalent Cd(1) and two equivalent Cd(2) atoms to form SeCd4 tetrahedra that share corners with two equivalent Te(1)Cd4 tetrahedra, corners with two equivalent Se(2)Cd4 tetrahedra, and corners with eight equivalent Se(1)Cd4 tetrahedra.