KCu2H2(SeO5)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form KO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Cu(1) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. H(1) is bonded in a single-bond geometry to one O(2) atom. Se(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted water-like geometry to one H(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one K(1), one Cu(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Cu(1) atoms.
KCu2H2(SeO5)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form KO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Both K(1)-O(1) bond lengths are 2.75 Å. All K(1)-O(3) bond lengths are 2.83 Å. Cu(1) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. Both Cu(1)-O(3) bond lengths are 2.18 Å. Both Cu(1)-O(4) bond lengths are 1.78 Å. H(1) is bonded in a single-bond geometry to one O(2) atom. The H(1)-O(2) bond length is 0.99 Å. Se(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. The Se(1)-O(1) bond length is 1.65 Å. The Se(1)-O(2) bond length is 1.80 Å. Both Se(1)-O(3) bond lengths are 1.67 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted water-like geometry to one H(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one K(1), one Cu(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Cu(1) atoms.