K crystallizes in the tetragonal P4/mmm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to eight equivalent K(2) atoms to form distorted edge-sharing KK8 hexagonal bipyramids. In the second K site, K(2) is bonded in a 7-coordinate geometry to two equivalent K(1) and five equivalent K(2) atoms.
K crystallizes in the tetragonal P4/mmm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to eight equivalent K(2) atoms to form distorted edge-sharing KK8 hexagonal bipyramids. All K(1)-K(2) bond lengths are 4.64 Å. In the second K site, K(2) is bonded in a 7-coordinate geometry to two equivalent K(1) and five equivalent K(2) atoms. There is one shorter (4.32 Å) and four longer (4.37 Å) K(2)-K(2) bond lengths.