K3MgSbS4 crystallizes in the trigonal R3m space group. K(1) is bonded in a 8-coordinate geometry to one Mg(1), one Sb(1), two equivalent S(1), and four equivalent S(2) atoms. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent K(1), one S(1), and three equivalent S(2) atoms. Sb(1) is bonded in a 3-coordinate geometry to three equivalent K(1) and three equivalent S(2) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to six equivalent K(1) and one Mg(1) atom. In the second S site, S(2) is bonded in a 6-coordinate geometry to four equivalent K(1), one Mg(1), and one Sb(1) atom.
K3MgSbS4 crystallizes in the trigonal R3m space group. K(1) is bonded in a 8-coordinate geometry to one Mg(1), one Sb(1), two equivalent S(1), and four equivalent S(2) atoms. The K(1)-Mg(1) bond length is 3.27 Å. The K(1)-Sb(1) bond length is 4.00 Å. There is one shorter (3.12 Å) and one longer (3.52 Å) K(1)-S(1) bond length. There are two shorter (3.39 Å) and two longer (3.60 Å) K(1)-S(2) bond lengths. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent K(1), one S(1), and three equivalent S(2) atoms. The Mg(1)-S(1) bond length is 2.30 Å. All Mg(1)-S(2) bond lengths are 2.54 Å. Sb(1) is bonded in a 3-coordinate geometry to three equivalent K(1) and three equivalent S(2) atoms. All Sb(1)-S(2) bond lengths are 2.46 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to six equivalent K(1) and one Mg(1) atom. In the second S site, S(2) is bonded in a 6-coordinate geometry to four equivalent K(1), one Mg(1), and one Sb(1) atom.