K3MgSbS4 crystallizes in the tetragonal I-4 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent S(1) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to four equivalent S(1) atoms. Mg(1) is bonded to four equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Sb(1)S4 tetrahedra. Sb(1) is bonded to four equivalent S(1) atoms to form distorted SbS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra. S(1) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), and one Sb(1) atom.
K3MgSbS4 crystallizes in the tetragonal I-4 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent S(1) atoms. There are two shorter (3.10 Å) and two longer (3.15 Å) K(1)-S(1) bond lengths. In the second K site, K(2) is bonded in a 4-coordinate geometry to four equivalent S(1) atoms. All K(2)-S(1) bond lengths are 3.23 Å. Mg(1) is bonded to four equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Sb(1)S4 tetrahedra. All Mg(1)-S(1) bond lengths are 2.50 Å. Sb(1) is bonded to four equivalent S(1) atoms to form distorted SbS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra. All Sb(1)-S(1) bond lengths are 2.68 Å. S(1) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Mg(1), and one Sb(1) atom.