Ca2Ta2SnO8 crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted edge-sharing TaO6 octahedra. Sn(1) is bonded in a see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ta(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ta(1) and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ca(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Ca(1) and one Ta(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ta trigonal pyramids.
Ca2Ta2SnO8 crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. There are a spread of Ca(1)-O(3) bond distances ranging from 2.30-2.77 Å. There are a spread of Ca(1)-O(4) bond distances ranging from 2.24-2.36 Å. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted edge-sharing TaO6 octahedra. The Ta(1)-O(2) bond length is 1.83 Å. The Ta(1)-O(4) bond length is 1.96 Å. There is one shorter (2.01 Å) and one longer (2.10 Å) Ta(1)-O(1) bond length. There is one shorter (2.03 Å) and one longer (2.35 Å) Ta(1)-O(3) bond length. Sn(1) is bonded in a see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. Both Sn(1)-O(1) bond lengths are 2.39 Å. Both Sn(1)-O(2) bond lengths are 2.43 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ta(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ta(1) and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ca(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Ca(1) and one Ta(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ta trigonal pyramids.