K2Sn2O3 crystallizes in the trigonal R-3m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent Sn(1) and six equivalent O(1) atoms to form distorted KSn2O6 hexagonal bipyramids that share corners with six equivalent K(1)Sn2O6 hexagonal bipyramids and corners with six equivalent O(1)K4Sn2 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second K site, K(2) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. Sn(1) is bonded in a 3-coordinate geometry to one K(1) and three equivalent O(1) atoms. O(1) is bonded to two equivalent K(1), two equivalent K(2), and two equivalent Sn(1) atoms to form distorted OK4Sn2 octahedra that share corners with two equivalent K(1)Sn2O6 hexagonal bipyramids, corners with twelve equivalent O(1)K4Sn2 octahedra, and faces with four equivalent O(1)K4Sn2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°.
K2Sn2O3 crystallizes in the trigonal R-3m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent Sn(1) and six equivalent O(1) atoms to form distorted KSn2O6 hexagonal bipyramids that share corners with six equivalent K(1)Sn2O6 hexagonal bipyramids and corners with six equivalent O(1)K4Sn2 octahedra. The corner-sharing octahedral tilt angles are 58°. Both K(1)-Sn(1) bond lengths are 3.66 Å. All K(1)-O(1) bond lengths are 3.01 Å. In the second K site, K(2) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. All K(2)-O(1) bond lengths are 2.94 Å. Sn(1) is bonded in a 3-coordinate geometry to one K(1) and three equivalent O(1) atoms. All Sn(1)-O(1) bond lengths are 2.04 Å. O(1) is bonded to two equivalent K(1), two equivalent K(2), and two equivalent Sn(1) atoms to form distorted OK4Sn2 octahedra that share corners with two equivalent K(1)Sn2O6 hexagonal bipyramids, corners with twelve equivalent O(1)K4Sn2 octahedra, and faces with four equivalent O(1)K4Sn2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°.