K4Cu(O10I)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(7), one O(8), and two equivalent O(9) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(7), and two equivalent O(6) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. There are ten inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to two equivalent K(2) and one I(1) atom. In the second O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(1) atom. In the third O site, O(8) is bonded in a bent 150 degrees geometry to one K(1) and one O(8) atom. In the fourth O site, O(1) is bonded in a distorted water-like geometry to one O(1) and one O(9) atom. In the fifth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to two equivalent K(1) and one O(1) atom. In the sixth O site, O(2) is bonded in a bent 120 degrees geometry to one K(1) and one O(10) atom. In the seventh O site, O(10) is bonded in a bent 150 degrees geometry to one K(1) and one O(2) atom. In the eighth O site, O(3) is bonded in a 3-coordinate geometry to one K(1), one K(2), and one I(1) atom. In the ninth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Cu(1), and one I(1) atom. In the tenth O site, O(5) is bonded in a water-like geometry to one Cu(1) and one I(1) atom. I(1) is bonded in a distorted trigonal bipyramidal geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom.
K4Cu(O10I)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(7), one O(8), and two equivalent O(9) atoms. The K(1)-O(10) bond length is 3.03 Å. The K(1)-O(2) bond length is 2.76 Å. The K(1)-O(3) bond length is 2.68 Å. The K(1)-O(4) bond length is 3.09 Å. The K(1)-O(7) bond length is 2.75 Å. The K(1)-O(8) bond length is 3.18 Å. There is one shorter (3.19 Å) and one longer (3.29 Å) K(1)-O(9) bond length. In the second K site, K(2) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(7), and two equivalent O(6) atoms. The K(2)-O(3) bond length is 2.93 Å. The K(2)-O(4) bond length is 2.78 Å. The K(2)-O(7) bond length is 2.84 Å. There is one shorter (3.01 Å) and one longer (3.14 Å) K(2)-O(6) bond length. Cu(1) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. Both Cu(1)-O(4) bond lengths are 1.84 Å. Both Cu(1)-O(5) bond lengths are 1.84 Å. There are ten inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to two equivalent K(2) and one I(1) atom. The O(6)-I(1) bond length is 1.82 Å. In the second O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one I(1) atom. The O(7)-I(1) bond length is 1.81 Å. In the third O site, O(8) is bonded in a bent 150 degrees geometry to one K(1) and one O(8) atom. The O(8)-O(8) bond length is 1.24 Å. In the fourth O site, O(1) is bonded in a distorted water-like geometry to one O(1) and one O(9) atom. The O(1)-O(1) bond length is 1.93 Å. The O(1)-O(9) bond length is 1.25 Å. In the fifth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to two equivalent K(1) and one O(1) atom. In the sixth O site, O(2) is bonded in a bent 120 degrees geometry to one K(1) and one O(10) atom. The O(2)-O(10) bond length is 1.26 Å. In the seventh O site, O(10) is bonded in a bent 150 degrees geometry to one K(1) and one O(2) atom. In the eighth O site, O(3) is bonded in a 3-coordinate geometry to one K(1), one K(2), and one I(1) atom. The O(3)-I(1) bond length is 1.83 Å. In the ninth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Cu(1), and one I(1) atom. The O(4)-I(1) bond length is 2.00 Å. In the tenth O site, O(5) is bonded in a water-like geometry to one Cu(1) and one I(1) atom. The O(5)-I(1) bond length is 1.94 Å. I(1) is bonded in a distorted trigonal bipyramidal geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom.