BaGdNbSnO6 crystallizes in the orthorhombic Pnnn space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share faces with four equivalent Gd(1)O6 octahedra and faces with four equivalent Nb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. Gd(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form GdO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 20-25°. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with six equivalent Gd(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 20-25°. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a square co-planar geometry to four equivalent O(2) atoms. In the second Sn site, Sn(2) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Gd(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), one Gd(1), one Nb(1), and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Gd(1), one Nb(1), and one Sn(2) atom.
BaGdNbSnO6 crystallizes in the orthorhombic Pnnn space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share faces with four equivalent Gd(1)O6 octahedra and faces with four equivalent Nb(1)O6 octahedra. All Ba(1)-O(1) bond lengths are 2.97 Å. All Ba(1)-O(2) bond lengths are 2.94 Å. All Ba(1)-O(3) bond lengths are 3.08 Å. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. All Ba(2)-O(1) bond lengths are 2.66 Å. All Ba(2)-O(3) bond lengths are 3.00 Å. Gd(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form GdO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 20-25°. Both Gd(1)-O(1) bond lengths are 2.27 Å. Both Gd(1)-O(2) bond lengths are 2.32 Å. Both Gd(1)-O(3) bond lengths are 2.32 Å. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with six equivalent Gd(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 20-25°. Both Nb(1)-O(1) bond lengths are 2.01 Å. Both Nb(1)-O(2) bond lengths are 2.05 Å. Both Nb(1)-O(3) bond lengths are 2.05 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a square co-planar geometry to four equivalent O(2) atoms. All Sn(1)-O(2) bond lengths are 2.54 Å. In the second Sn site, Sn(2) is bonded in a square co-planar geometry to four equivalent O(3) atoms. All Sn(2)-O(3) bond lengths are 2.54 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(2), one Gd(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), one Gd(1), one Nb(1), and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Gd(1), one Nb(1), and one Sn(2) atom.