Y2TiSnO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(2) atoms. In the second Y site, Y(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted YO8 hexagonal bipyramids that share edges with two equivalent Y(2)O8 hexagonal bipyramids, edges with two equivalent Sn(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. Ti(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with four equivalent Sn(1)O6 octahedra, and edges with four equivalent Y(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-51°. Sn(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form SnO6 octahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with four equivalent Ti(1)O6 octahedra, and edges with two equivalent Y(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-57°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Y(2) atoms to form OY4 tetrahedra that share corners with two equivalent O(4)Y2Sn2 tetrahedra, corners with four equivalent O(1)Y4 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(4)Y2Sn2 tetrahedra, and edges with four equivalent O(2)Y2TiSn tetrahedra. In the second O site, O(2) is bonded to one Y(1), one Y(2), one Ti(1), and one Sn(1) atom to form distorted OY2TiSn tetrahedra that share corners with two equivalent O(4)Y2Sn2 tetrahedra, corners with two equivalent O(1)Y4 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(4)Y2Sn2 tetrahedra,  an edgeedge with one O(1)Y4 tetrahedra, and edges with two equivalent O(2)Y2TiSn tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Y(2) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Y(1) and two equivalent Sn(1) atoms to form OY2Sn2 tetrahedra that share corners with two equivalent O(1)Y4 tetrahedra, corners with four equivalent O(4)Y2Sn2 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(1)Y4 tetrahedra, and edges with four equivalent O(2)Y2TiSn tetrahedra.
Y2TiSnO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(2) atoms. Both Y(1)-O(1) bond lengths are 2.25 Å. Both Y(1)-O(4) bond lengths are 2.44 Å. All Y(1)-O(2) bond lengths are 2.53 Å. In the second Y site, Y(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted YO8 hexagonal bipyramids that share edges with two equivalent Y(2)O8 hexagonal bipyramids, edges with two equivalent Sn(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. Both Y(2)-O(1) bond lengths are 2.23 Å. Both Y(2)-O(3) bond lengths are 2.61 Å. All Y(2)-O(2) bond lengths are 2.48 Å. Ti(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with four equivalent Sn(1)O6 octahedra, and edges with four equivalent Y(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-51°. Both Ti(1)-O(3) bond lengths are 1.97 Å. All Ti(1)-O(2) bond lengths are 1.99 Å. Sn(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form SnO6 octahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with four equivalent Ti(1)O6 octahedra, and edges with two equivalent Y(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-57°. Both Sn(1)-O(4) bond lengths are 2.08 Å. All Sn(1)-O(2) bond lengths are 2.07 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Y(2) atoms to form OY4 tetrahedra that share corners with two equivalent O(4)Y2Sn2 tetrahedra, corners with four equivalent O(1)Y4 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(4)Y2Sn2 tetrahedra, and edges with four equivalent O(2)Y2TiSn tetrahedra. In the second O site, O(2) is bonded to one Y(1), one Y(2), one Ti(1), and one Sn(1) atom to form distorted OY2TiSn tetrahedra that share corners with two equivalent O(4)Y2Sn2 tetrahedra, corners with two equivalent O(1)Y4 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(4)Y2Sn2 tetrahedra,  an edgeedge with one O(1)Y4 tetrahedra, and edges with two equivalent O(2)Y2TiSn tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Y(2) and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Y(1) and two equivalent Sn(1) atoms to form OY2Sn2 tetrahedra that share corners with two equivalent O(1)Y4 tetrahedra, corners with four equivalent O(4)Y2Sn2 tetrahedra, corners with eight equivalent O(2)Y2TiSn tetrahedra,  an edgeedge with one O(1)Y4 tetrahedra, and edges with four equivalent O(2)Y2TiSn tetrahedra.