KO3 is Baddeleyite-like structured and crystallizes in the orthorhombic Imm2 space group. K(1) is bonded to one O(2) and six equivalent O(1) atoms to form distorted KO7 pentagonal bipyramids that share corners with eight equivalent K(1)O7 pentagonal bipyramids, corners with two equivalent O(1)K3O tetrahedra, and edges with two equivalent K(1)O7 pentagonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent K(1) and one O(2) atom to form OK3O tetrahedra that share  a cornercorner with one K(1)O7 pentagonal bipyramid, corners with twelve equivalent O(1)K3O tetrahedra, and edges with two equivalent O(1)K3O tetrahedra. In the second O site, O(2) is bonded in a trigonal planar geometry to one K(1) and two equivalent O(1) atoms.
KO3 is Baddeleyite-like structured and crystallizes in the orthorhombic Imm2 space group. K(1) is bonded to one O(2) and six equivalent O(1) atoms to form distorted KO7 pentagonal bipyramids that share corners with eight equivalent K(1)O7 pentagonal bipyramids, corners with two equivalent O(1)K3O tetrahedra, and edges with two equivalent K(1)O7 pentagonal bipyramids. The K(1)-O(2) bond length is 3.06 Å. There are four shorter (2.81 Å) and two longer (2.84 Å) K(1)-O(1) bond lengths. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent K(1) and one O(2) atom to form OK3O tetrahedra that share  a cornercorner with one K(1)O7 pentagonal bipyramid, corners with twelve equivalent O(1)K3O tetrahedra, and edges with two equivalent O(1)K3O tetrahedra. The O(1)-O(2) bond length is 1.37 Å. In the second O site, O(2) is bonded in a trigonal planar geometry to one K(1) and two equivalent O(1) atoms.