K8MgMn4O16 crystallizes in the triclinic P1 space group. There are eight inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(15), one O(2), one O(4), one O(8), and one O(9) atom. In the second K site, K(2) is bonded in a 5-coordinate geometry to one O(12), one O(2), one O(3), one O(4), and one O(8) atom. In the third K site, K(3) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(14), one O(4), one O(5), and one O(6) atom. In the fourth K site, K(4) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(7) atom. In the fifth K site, K(5) is bonded to one O(1), one O(10), one O(13), one O(14), one O(16), one O(6), and one O(9) atom to form distorted KO7 pentagonal bipyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(3)O4 tetrahedra, corners with two equivalent Mn(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O4 tetrahedra. In the sixth K site, K(6) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(2), one O(3), one O(6), and one O(7) atom. In the seventh K site, K(7) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(13), one O(14), one O(15), one O(5), and one O(9) atom. In the eighth K site, K(8) is bonded in a 5-coordinate geometry to one O(13), one O(15), one O(16), one O(7), and one O(9) atom. Mg(1) is bonded to one O(1), one O(11), one O(7), and one O(8) atom to form distorted MgO4 tetrahedra that share  a cornercorner with one K(5)O7 pentagonal bipyramid,  a cornercorner with one Mn(3)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O4 tetrahedra. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(7), and one O(9) atom to form MnO4 tetrahedra that share  an edgeedge with one K(5)O7 pentagonal bipyramid and  an edgeedge with one Mg(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(13), one O(3), one O(5), and one O(6) atom to form MnO4 tetrahedra that share corners with two equivalent K(5)O7 pentagonal bipyramids. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form MnO4 tetrahedra that share  a cornercorner with one K(5)O7 pentagonal bipyramid and  a cornercorner with one Mg(1)O4 tetrahedra. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(15), one O(16), and one O(8) atom to form MnO4 tetrahedra that share corners with two equivalent K(5)O7 pentagonal bipyramids and  a cornercorner with one Mg(1)O4 tetrahedra. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), one K(4), one K(5), one Mg(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(4), one K(6), and one Mn(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(2), one K(4), one K(6), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one K(2), one K(3), one K(4), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(3), one K(7), and one Mn(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one K(3), one K(5), one K(6), and one Mn(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one K(4), one K(6), one K(8), one Mg(1), and one Mn(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one Mg(1), and one Mn(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one K(1), one K(5), one K(7), one K(8), and one Mn(1) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one K(1), one K(3), one K(5), one K(7), and one Mn(4) atom. In the eleventh O site, O(11) is bonded in a distorted bent 120 degrees geometry to one K(3), one K(6), one Mg(1), and one Mn(3) atom. In the twelfth O site, O(12) is bonded in a 1-coordinate geometry to one K(2), one K(6), one K(7), and one Mn(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one K(5), one K(6), one K(7), one K(8), and one Mn(2) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one K(3), one K(5), one K(7), and one Mn(3) atom. In the fifteenth O site, O(15) is bonded in a distorted single-bond geometry to one K(1), one K(7), one K(8), and one Mn(4) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one K(5), one K(8), and one Mn(4) atom.
K8MgMn4O16 crystallizes in the triclinic P1 space group. There are eight inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(15), one O(2), one O(4), one O(8), and one O(9) atom. The K(1)-O(1) bond length is 3.02 Å. The K(1)-O(10) bond length is 2.83 Å. The K(1)-O(15) bond length is 2.67 Å. The K(1)-O(2) bond length is 2.77 Å. The K(1)-O(4) bond length is 3.28 Å. The K(1)-O(8) bond length is 2.94 Å. The K(1)-O(9) bond length is 3.06 Å. In the second K site, K(2) is bonded in a 5-coordinate geometry to one O(12), one O(2), one O(3), one O(4), and one O(8) atom. The K(2)-O(12) bond length is 2.72 Å. The K(2)-O(2) bond length is 2.86 Å. The K(2)-O(3) bond length is 2.73 Å. The K(2)-O(4) bond length is 2.72 Å. The K(2)-O(8) bond length is 2.88 Å. In the third K site, K(3) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(14), one O(4), one O(5), and one O(6) atom. The K(3)-O(10) bond length is 3.02 Å. The K(3)-O(11) bond length is 3.35 Å. The K(3)-O(14) bond length is 2.78 Å. The K(3)-O(4) bond length is 3.03 Å. The K(3)-O(5) bond length is 2.75 Å. The K(3)-O(6) bond length is 2.82 Å. In the fourth K site, K(4) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(7) atom. The K(4)-O(1) bond length is 2.66 Å. The K(4)-O(2) bond length is 2.82 Å. The K(4)-O(3) bond length is 2.60 Å. The K(4)-O(4) bond length is 2.63 Å. The K(4)-O(7) bond length is 2.77 Å. In the fifth K site, K(5) is bonded to one O(1), one O(10), one O(13), one O(14), one O(16), one O(6), and one O(9) atom to form distorted KO7 pentagonal bipyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(3)O4 tetrahedra, corners with two equivalent Mn(2)O4 tetrahedra, corners with two equivalent Mn(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O4 tetrahedra. The K(5)-O(1) bond length is 2.90 Å. The K(5)-O(10) bond length is 2.78 Å. The K(5)-O(13) bond length is 2.76 Å. The K(5)-O(14) bond length is 2.85 Å. The K(5)-O(16) bond length is 2.91 Å. The K(5)-O(6) bond length is 2.87 Å. The K(5)-O(9) bond length is 2.99 Å. In the sixth K site, K(6) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(2), one O(3), one O(6), and one O(7) atom. The K(6)-O(11) bond length is 2.83 Å. The K(6)-O(12) bond length is 2.70 Å. The K(6)-O(13) bond length is 2.97 Å. The K(6)-O(2) bond length is 3.28 Å. The K(6)-O(3) bond length is 2.81 Å. The K(6)-O(6) bond length is 3.05 Å. The K(6)-O(7) bond length is 3.11 Å. In the seventh K site, K(7) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(13), one O(14), one O(15), one O(5), and one O(9) atom. The K(7)-O(10) bond length is 2.86 Å. The K(7)-O(12) bond length is 3.07 Å. The K(7)-O(13) bond length is 2.85 Å. The K(7)-O(14) bond length is 2.76 Å. The K(7)-O(15) bond length is 3.02 Å. The K(7)-O(5) bond length is 2.81 Å. The K(7)-O(9) bond length is 2.77 Å. In the eighth K site, K(8) is bonded in a 5-coordinate geometry to one O(13), one O(15), one O(16), one O(7), and one O(9) atom. The K(8)-O(13) bond length is 2.88 Å. The K(8)-O(15) bond length is 2.74 Å. The K(8)-O(16) bond length is 2.73 Å. The K(8)-O(7) bond length is 2.96 Å. The K(8)-O(9) bond length is 2.75 Å. Mg(1) is bonded to one O(1), one O(11), one O(7), and one O(8) atom to form distorted MgO4 tetrahedra that share  a cornercorner with one K(5)O7 pentagonal bipyramid,  a cornercorner with one Mn(3)O4 tetrahedra,  a cornercorner with one Mn(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O4 tetrahedra. The Mg(1)-O(1) bond length is 1.98 Å. The Mg(1)-O(11) bond length is 1.94 Å. The Mg(1)-O(7) bond length is 2.02 Å. The Mg(1)-O(8) bond length is 1.96 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(7), and one O(9) atom to form MnO4 tetrahedra that share  an edgeedge with one K(5)O7 pentagonal bipyramid and  an edgeedge with one Mg(1)O4 tetrahedra. The Mn(1)-O(1) bond length is 1.77 Å. The Mn(1)-O(2) bond length is 1.68 Å. The Mn(1)-O(7) bond length is 1.77 Å. The Mn(1)-O(9) bond length is 1.68 Å. In the second Mn site, Mn(2) is bonded to one O(13), one O(3), one O(5), and one O(6) atom to form MnO4 tetrahedra that share corners with two equivalent K(5)O7 pentagonal bipyramids. The Mn(2)-O(13) bond length is 1.67 Å. The Mn(2)-O(3) bond length is 1.67 Å. The Mn(2)-O(5) bond length is 1.65 Å. The Mn(2)-O(6) bond length is 1.66 Å. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form MnO4 tetrahedra that share  a cornercorner with one K(5)O7 pentagonal bipyramid and  a cornercorner with one Mg(1)O4 tetrahedra. The Mn(3)-O(11) bond length is 1.76 Å. The Mn(3)-O(12) bond length is 1.68 Å. The Mn(3)-O(14) bond length is 1.69 Å. The Mn(3)-O(4) bond length is 1.70 Å. In the fourth Mn site, Mn(4) is bonded to one O(10), one O(15), one O(16), and one O(8) atom to form MnO4 tetrahedra that share corners with two equivalent K(5)O7 pentagonal bipyramids and  a cornercorner with one Mg(1)O4 tetrahedra. The Mn(4)-O(10) bond length is 1.69 Å. The Mn(4)-O(15) bond length is 1.68 Å. The Mn(4)-O(16) bond length is 1.66 Å. The Mn(4)-O(8) bond length is 1.75 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), one K(4), one K(5), one Mg(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(4), one K(6), and one Mn(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(2), one K(4), one K(6), and one Mn(2) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one K(2), one K(3), one K(4), and one Mn(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(3), one K(7), and one Mn(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one K(3), one K(5), one K(6), and one Mn(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one K(4), one K(6), one K(8), one Mg(1), and one Mn(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one Mg(1), and one Mn(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one K(1), one K(5), one K(7), one K(8), and one Mn(1) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one K(1), one K(3), one K(5), one K(7), and one Mn(4) atom. In the eleventh O site, O(11) is bonded in a distorted bent 120 degrees geometry to one K(3), one K(6), one Mg(1), and one Mn(3) atom. In the twelfth O site, O(12) is bonded in a 1-coordinate geometry to one K(2), one K(6), one K(7), and one Mn(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one K(5), one K(6), one K(7), one K(8), and one Mn(2) atom. In the fourteenth O site, O(14) is bonded in a distorted single-bond geometry to one K(3), one K(5), one K(7), and one Mn(3) atom. In the fifteenth O site, O(15) is bonded in a distorted single-bond geometry to one K(1), one K(7), one K(8), and one Mn(4) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one K(5), one K(8), and one Mn(4) atom.