K2MgMo2P2(O5Cl)2 crystallizes in the monoclinic Cm space group. K(1) is bonded in a 2-coordinate geometry to one O(5), one O(6), and one Cl(2) atom. Mg(1) is bonded to one O(3), two equivalent O(1), one Cl(1), and one Cl(2) atom to form distorted MgCl2O3 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 5-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(4), and one Cl(2) atom. In the second Mo site, Mo(2) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(2), and two equivalent O(5) atoms. P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)Cl2O3 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mo(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mo(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one Mo(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Mo(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Mo(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent K(1) and one Mo(1) atom. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 1-coordinate geometry to one Mg(1) atom. In the second Cl site, Cl(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one Mg(1), and one Mo(1) atom.
K2MgMo2P2(O5Cl)2 crystallizes in the monoclinic Cm space group. K(1) is bonded in a 2-coordinate geometry to one O(5), one O(6), and one Cl(2) atom. The K(1)-O(5) bond length is 2.67 Å. The K(1)-O(6) bond length is 2.73 Å. The K(1)-Cl(2) bond length is 3.23 Å. Mg(1) is bonded to one O(3), two equivalent O(1), one Cl(1), and one Cl(2) atom to form distorted MgCl2O3 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra. The Mg(1)-O(3) bond length is 1.97 Å. Both Mg(1)-O(1) bond lengths are 2.05 Å. The Mg(1)-Cl(1) bond length is 2.43 Å. The Mg(1)-Cl(2) bond length is 2.58 Å. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 5-coordinate geometry to one O(6), two equivalent O(1), two equivalent O(4), and one Cl(2) atom. The Mo(1)-O(6) bond length is 1.81 Å. Both Mo(1)-O(1) bond lengths are 2.18 Å. Both Mo(1)-O(4) bond lengths are 2.10 Å. The Mo(1)-Cl(2) bond length is 2.73 Å. In the second Mo site, Mo(2) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(2), and two equivalent O(5) atoms. The Mo(2)-O(3) bond length is 1.83 Å. Both Mo(2)-O(2) bond lengths are 2.10 Å. Both Mo(2)-O(5) bond lengths are 2.12 Å. P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)Cl2O3 trigonal bipyramid. The P(1)-O(1) bond length is 1.57 Å. The P(1)-O(2) bond length is 1.53 Å. The P(1)-O(4) bond length is 1.55 Å. The P(1)-O(5) bond length is 1.55 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mo(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mo(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one Mo(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Mo(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one K(1), one Mo(2), and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent K(1) and one Mo(1) atom. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 1-coordinate geometry to one Mg(1) atom. In the second Cl site, Cl(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one Mg(1), and one Mo(1) atom.