Mg2Nb2SnO8 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. Nb(1) is bonded in a 6-coordinate geometry to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms. Sn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted edge-sharing SnO6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Nb(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent Sn(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Mg(1) and one Nb(1) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids.
Mg2Nb2SnO8 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. There are a spread of Mg(1)-O(3) bond distances ranging from 2.04-2.48 Å. There are two shorter (2.04 Å) and one longer (2.13 Å) Mg(1)-O(4) bond length. Nb(1) is bonded in a 6-coordinate geometry to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms. The Nb(1)-O(2) bond length is 1.85 Å. The Nb(1)-O(4) bond length is 1.98 Å. There is one shorter (1.97 Å) and one longer (2.08 Å) Nb(1)-O(1) bond length. There is one shorter (2.07 Å) and one longer (2.48 Å) Nb(1)-O(3) bond length. Sn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted edge-sharing SnO6 octahedra. Both Sn(1)-O(1) bond lengths are 2.47 Å. There are two shorter (2.44 Å) and two longer (2.52 Å) Sn(1)-O(2) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Nb(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent Sn(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Mg(1) and one Nb(1) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids.