K3H(SeO4)2 crystallizes in the monoclinic Cc space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(6), one O(8), two equivalent O(1), two equivalent O(3), and two equivalent O(7) atoms. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(1), one O(3), one O(5), one O(7), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms. In the third K site, K(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. H(1) is bonded in a linear geometry to one O(5) and one O(6) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(5), and one O(7) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(6), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a 1-coordinate geometry to one K(2), one H(1), and one Se(1) atom. In the second O site, O(6) is bonded in a distorted water-like geometry to one K(1), one H(1), and one Se(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the fourth O site, O(8) is bonded in a distorted single-bond geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom. In the seventh O site, O(3) is bonded in a 1-coordinate geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the eighth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom.
K3H(SeO4)2 crystallizes in the monoclinic Cc space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(6), one O(8), two equivalent O(1), two equivalent O(3), and two equivalent O(7) atoms. The K(1)-O(2) bond length is 2.82 Å. The K(1)-O(4) bond length is 3.31 Å. The K(1)-O(6) bond length is 3.02 Å. The K(1)-O(8) bond length is 2.85 Å. There is one shorter (3.05 Å) and one longer (3.15 Å) K(1)-O(1) bond length. There is one shorter (3.07 Å) and one longer (3.21 Å) K(1)-O(3) bond length. There is one shorter (2.99 Å) and one longer (3.17 Å) K(1)-O(7) bond length. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(1), one O(3), one O(5), one O(7), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms. The K(2)-O(1) bond length is 2.84 Å. The K(2)-O(3) bond length is 3.36 Å. The K(2)-O(5) bond length is 2.99 Å. The K(2)-O(7) bond length is 2.87 Å. There is one shorter (3.05 Å) and one longer (3.14 Å) K(2)-O(2) bond length. There is one shorter (3.05 Å) and one longer (3.19 Å) K(2)-O(4) bond length. There is one shorter (2.98 Å) and one longer (3.17 Å) K(2)-O(8) bond length. In the third K site, K(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. The K(3)-O(1) bond length is 2.98 Å. The K(3)-O(2) bond length is 2.96 Å. The K(3)-O(3) bond length is 2.78 Å. The K(3)-O(4) bond length is 2.76 Å. The K(3)-O(7) bond length is 2.96 Å. The K(3)-O(8) bond length is 2.95 Å. H(1) is bonded in a linear geometry to one O(5) and one O(6) atom. The H(1)-O(5) bond length is 1.09 Å. The H(1)-O(6) bond length is 1.41 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(5), and one O(7) atom. The Se(1)-O(1) bond length is 1.66 Å. The Se(1)-O(3) bond length is 1.65 Å. The Se(1)-O(5) bond length is 1.77 Å. The Se(1)-O(7) bond length is 1.66 Å. In the second Se site, Se(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(6), and one O(8) atom. The Se(2)-O(2) bond length is 1.67 Å. The Se(2)-O(4) bond length is 1.67 Å. The Se(2)-O(6) bond length is 1.72 Å. The Se(2)-O(8) bond length is 1.67 Å. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a 1-coordinate geometry to one K(2), one H(1), and one Se(1) atom. In the second O site, O(6) is bonded in a distorted water-like geometry to one K(1), one H(1), and one Se(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the fourth O site, O(8) is bonded in a distorted single-bond geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom. In the fifth O site, O(1) is bonded in a distorted single-bond geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the sixth O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom. In the seventh O site, O(3) is bonded in a 1-coordinate geometry to one K(2), one K(3), two equivalent K(1), and one Se(1) atom. In the eighth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one K(3), two equivalent K(2), and one Se(2) atom.