K2MgMnH4(O7I2)2 crystallizes in the triclinic P1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(2), one O(6), one O(7), one O(8), and one O(9) atom. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(5), one O(6), and one O(7) atom. Mg(1) is bonded to one O(1), one O(12), one O(14), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 69°. Mn(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(8), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra. There are four inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(10) and one O(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(10) and one O(4) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(5) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(1) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one H(4) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one K(1), one Mn(1), and one I(3) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one I(4) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one H(2), and one I(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(2), one H(1), one H(3), and one I(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one K(1), one K(2), and one I(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one Mn(1), and one I(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one Mn(1), and one I(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Mn(1), one H(1), and one H(2) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(3) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Mg(1), and one I(4) atom. In the thirteenth O site, O(13) is bonded in a 1-coordinate geometry to one K(2) and one I(1) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one K(2), one Mg(1), and one I(2) atom. There are four inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one O(13), one O(6), and one O(8) atom. In the second I site, I(2) is bonded in a distorted trigonal non-coplanar geometry to one O(14), one O(7), and one O(9) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one O(11), one O(2), and one O(4) atom. In the fourth I site, I(4) is bonded in a distorted T-shaped geometry to one O(12), one O(3), and one O(5) atom.
K2MgMnH4(O7I2)2 crystallizes in the triclinic P1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(2), one O(6), one O(7), one O(8), and one O(9) atom. The K(1)-O(11) bond length is 2.90 Å. The K(1)-O(12) bond length is 2.82 Å. The K(1)-O(2) bond length is 3.12 Å. The K(1)-O(6) bond length is 2.68 Å. The K(1)-O(7) bond length is 3.03 Å. The K(1)-O(8) bond length is 2.88 Å. The K(1)-O(9) bond length is 3.31 Å. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(5), one O(6), and one O(7) atom. The K(2)-O(11) bond length is 2.81 Å. The K(2)-O(12) bond length is 2.83 Å. The K(2)-O(13) bond length is 2.81 Å. The K(2)-O(14) bond length is 3.10 Å. The K(2)-O(5) bond length is 2.65 Å. The K(2)-O(6) bond length is 2.72 Å. The K(2)-O(7) bond length is 2.88 Å. Mg(1) is bonded to one O(1), one O(12), one O(14), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 69°. The Mg(1)-O(1) bond length is 1.93 Å. The Mg(1)-O(12) bond length is 1.96 Å. The Mg(1)-O(14) bond length is 2.03 Å. The Mg(1)-O(4) bond length is 2.00 Å. Mn(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(8), and one O(9) atom to form MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra. The Mn(1)-O(1) bond length is 2.11 Å. The Mn(1)-O(10) bond length is 2.15 Å. The Mn(1)-O(2) bond length is 2.27 Å. The Mn(1)-O(3) bond length is 2.26 Å. The Mn(1)-O(8) bond length is 2.31 Å. The Mn(1)-O(9) bond length is 2.38 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(10) and one O(5) atom. The H(1)-O(10) bond length is 1.02 Å. The H(1)-O(5) bond length is 1.64 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(10) and one O(4) atom. The H(2)-O(10) bond length is 0.99 Å. The H(2)-O(4) bond length is 1.73 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(5) atom. The H(3)-O(5) bond length is 0.99 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(1) atom. The H(4)-O(1) bond length is 0.99 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Mn(1), and one H(4) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one K(1), one Mn(1), and one I(3) atom. The O(2)-I(3) bond length is 1.84 Å. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mn(1) and one I(4) atom. The O(3)-I(4) bond length is 1.93 Å. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one H(2), and one I(3) atom. The O(4)-I(3) bond length is 1.86 Å. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(2), one H(1), one H(3), and one I(4) atom. The O(5)-I(4) bond length is 2.32 Å. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one K(1), one K(2), and one I(1) atom. The O(6)-I(1) bond length is 1.81 Å. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(2) atom. The O(7)-I(2) bond length is 1.82 Å. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one Mn(1), and one I(1) atom. The O(8)-I(1) bond length is 1.84 Å. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one Mn(1), and one I(2) atom. The O(9)-I(2) bond length is 1.83 Å. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Mn(1), one H(1), and one H(2) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(3) atom. The O(11)-I(3) bond length is 1.82 Å. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Mg(1), and one I(4) atom. The O(12)-I(4) bond length is 1.98 Å. In the thirteenth O site, O(13) is bonded in a 1-coordinate geometry to one K(2) and one I(1) atom. The O(13)-I(1) bond length is 1.85 Å. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one K(2), one Mg(1), and one I(2) atom. The O(14)-I(2) bond length is 1.87 Å. There are four inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one O(13), one O(6), and one O(8) atom. In the second I site, I(2) is bonded in a distorted trigonal non-coplanar geometry to one O(14), one O(7), and one O(9) atom. In the third I site, I(3) is bonded in a 3-coordinate geometry to one O(11), one O(2), and one O(4) atom. In the fourth I site, I(4) is bonded in a distorted T-shaped geometry to one O(12), one O(3), and one O(5) atom.