KB3SeO7 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms. There are three inequivalent B sites. In the first B site, B(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(4), and one O(7) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one K(1), one B(1), and one B(2) atom. In the second O site, O(5) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the third O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the fourth O site, O(7) is bonded in a bent 120 degrees geometry to one B(1) and one B(3) atom. In the fifth O site, O(1) is bonded in a 3-coordinate geometry to one K(1), one B(1), and one Se(1) atom. In the sixth O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent K(1) and one Se(1) atom. In the seventh O site, O(3) is bonded in a 2-coordinate geometry to two equivalent K(1), one B(1), and one Se(1) atom.
KB3SeO7 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms. The K(1)-O(1) bond length is 2.86 Å. The K(1)-O(4) bond length is 3.00 Å. The K(1)-O(5) bond length is 2.76 Å. The K(1)-O(6) bond length is 3.08 Å. There is one shorter (2.72 Å) and one longer (2.82 Å) K(1)-O(2) bond length. There is one shorter (2.98 Å) and one longer (3.09 Å) K(1)-O(3) bond length. There are three inequivalent B sites. In the first B site, B(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(4), and one O(7) atom. The B(1)-O(1) bond length is 1.49 Å. The B(1)-O(3) bond length is 1.51 Å. The B(1)-O(4) bond length is 1.47 Å. The B(1)-O(7) bond length is 1.48 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. The B(2)-O(4) bond length is 1.35 Å. The B(2)-O(5) bond length is 1.40 Å. The B(2)-O(6) bond length is 1.38 Å. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. The B(3)-O(5) bond length is 1.39 Å. The B(3)-O(6) bond length is 1.38 Å. The B(3)-O(7) bond length is 1.36 Å. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. The Se(1)-O(1) bond length is 1.80 Å. The Se(1)-O(2) bond length is 1.65 Å. The Se(1)-O(3) bond length is 1.79 Å. There are seven inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one K(1), one B(1), and one B(2) atom. In the second O site, O(5) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the third O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the fourth O site, O(7) is bonded in a bent 120 degrees geometry to one B(1) and one B(3) atom. In the fifth O site, O(1) is bonded in a 3-coordinate geometry to one K(1), one B(1), and one Se(1) atom. In the sixth O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent K(1) and one Se(1) atom. In the seventh O site, O(3) is bonded in a 2-coordinate geometry to two equivalent K(1), one B(1), and one Se(1) atom.