Ba2MgLuNbO6 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one Mg(1), one O(3), two equivalent O(2), two equivalent O(4), and four equivalent O(1) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Ba(2), one O(3), and two equivalent O(2) atoms. Lu(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form LuO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NbO6 octahedra that share corners with six equivalent Lu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), two equivalent Ba(2), one Lu(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Lu(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Lu(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ba(1), two equivalent Ba(2), one Lu(1), and one Nb(1) atom.
Ba2MgLuNbO6 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. The Ba(1)-O(4) bond length is 3.03 Å. Both Ba(1)-O(1) bond lengths are 3.08 Å. Both Ba(1)-O(3) bond lengths are 3.00 Å. There are two shorter (2.99 Å) and two longer (3.01 Å) Ba(1)-O(2) bond lengths. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one Mg(1), one O(3), two equivalent O(2), two equivalent O(4), and four equivalent O(1) atoms. The Ba(2)-Mg(1) bond length is 2.90 Å. The Ba(2)-O(3) bond length is 2.52 Å. Both Ba(2)-O(2) bond lengths are 2.52 Å. Both Ba(2)-O(4) bond lengths are 3.15 Å. There are two shorter (3.11 Å) and two longer (3.16 Å) Ba(2)-O(1) bond lengths. Mg(1) is bonded in a 3-coordinate geometry to one Ba(2), one O(3), and two equivalent O(2) atoms. The Mg(1)-O(3) bond length is 1.95 Å. Both Mg(1)-O(2) bond lengths are 1.95 Å. Lu(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form LuO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. The Lu(1)-O(3) bond length is 2.45 Å. The Lu(1)-O(4) bond length is 2.18 Å. Both Lu(1)-O(1) bond lengths are 2.17 Å. Both Lu(1)-O(2) bond lengths are 2.50 Å. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NbO6 octahedra that share corners with six equivalent Lu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. The Nb(1)-O(3) bond length is 2.34 Å. The Nb(1)-O(4) bond length is 2.00 Å. Both Nb(1)-O(1) bond lengths are 2.01 Å. Both Nb(1)-O(2) bond lengths are 2.29 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), two equivalent Ba(2), one Lu(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Lu(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(2), two equivalent Ba(1), one Mg(1), one Lu(1), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ba(1), two equivalent Ba(2), one Lu(1), and one Nb(1) atom.