BaEuNbSnO6 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 Nb(1)O6 octahedra and faces with four equivalent Sn(1)O6 octahedra. In the second Ba site, Ba(2) is bonded in a distorted square co-planar geometry to four equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a distorted square co-planar geometry to four equivalent O(2) atoms. In the second Eu site, Eu(2) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. 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 Sn(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 27-31°. Sn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SnO6 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 27-31°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Eu(2), one Nb(1), and one Sn(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Eu(1), one Nb(1), and one Sn(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Nb(1), and one Sn(1) atom.
BaEuNbSnO6 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 Nb(1)O6 octahedra and faces with four equivalent Sn(1)O6 octahedra. All Ba(1)-O(1) bond lengths are 2.98 Å. All Ba(1)-O(2) bond lengths are 3.02 Å. All Ba(1)-O(3) bond lengths are 3.02 Å. In the second Ba site, Ba(2) is bonded in a distorted square co-planar geometry to four equivalent O(2) and four equivalent O(3) atoms. All Ba(2)-O(2) bond lengths are 3.10 Å. All Ba(2)-O(3) bond lengths are 2.54 Å. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a distorted square co-planar geometry to four equivalent O(2) atoms. All Eu(1)-O(2) bond lengths are 2.41 Å. In the second Eu site, Eu(2) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. All Eu(2)-O(1) bond lengths are 2.40 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 Sn(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 27-31°. Both Nb(1)-O(1) bond lengths are 2.09 Å. Both Nb(1)-O(2) bond lengths are 2.07 Å. Both Nb(1)-O(3) bond lengths are 1.99 Å. Sn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SnO6 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 27-31°. Both Sn(1)-O(1) bond lengths are 2.37 Å. Both Sn(1)-O(2) bond lengths are 2.36 Å. Both Sn(1)-O(3) bond lengths are 2.31 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Eu(2), one Nb(1), and one Sn(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Eu(1), one Nb(1), and one Sn(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Nb(1), and one Sn(1) atom.