Ba6MgCr2O10 crystallizes in the triclinic P1 space group. There are six inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(4), one O(7), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. In the third Ba site, Ba(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. In the fifth Ba site, Ba(5) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), one O(8), and one O(9) atom. In the sixth Ba site, Ba(6) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom. Mg(1) is bonded to one O(2), one O(5), one O(6), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Cr(2)O4 tetrahedra and  an edgeedge with one Cr(1)O4 trigonal pyramid. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(4), one O(5), one O(8), and one O(9) atom to form distorted CrO4 trigonal pyramids that share  an edgeedge with one Mg(1)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(10), one O(3), one O(6), and one O(7) atom to form distorted CrO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Ba(6) atom to form a mixture of distorted corner and edge-sharing OBa6 octahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Ba(6), and one Mg(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), and one Cr(1) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(3), one Ba(4), one Ba(6), one Mg(1), and one Cr(1) atom. In the sixth O site, O(6) is bonded to one Ba(3), one Ba(5), one Ba(6), one Mg(1), and one Cr(2) atom to form a mixture of distorted corner and edge-sharing OBa3MgCr square pyramids. The corner-sharing octahedral tilt angles are 58°. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Ba(5), one Ba(6), and one Cr(2) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Mg(1), and one Cr(1) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(5), one Ba(6), and one Cr(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), and one Cr(2) atom.
Ba6MgCr2O10 crystallizes in the triclinic P1 space group. There are six inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(4), one O(7), and one O(9) atom. The Ba(1)-O(1) bond length is 2.60 Å. The Ba(1)-O(10) bond length is 2.69 Å. The Ba(1)-O(4) bond length is 2.64 Å. The Ba(1)-O(7) bond length is 2.75 Å. The Ba(1)-O(9) bond length is 2.86 Å. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. The Ba(2)-O(1) bond length is 2.83 Å. The Ba(2)-O(10) bond length is 2.74 Å. The Ba(2)-O(2) bond length is 2.63 Å. The Ba(2)-O(3) bond length is 3.24 Å. The Ba(2)-O(4) bond length is 2.66 Å. The Ba(2)-O(7) bond length is 3.17 Å. The Ba(2)-O(8) bond length is 3.24 Å. The Ba(2)-O(9) bond length is 3.21 Å. In the third Ba site, Ba(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. The Ba(3)-O(1) bond length is 2.62 Å. The Ba(3)-O(10) bond length is 3.01 Å. The Ba(3)-O(3) bond length is 2.69 Å. The Ba(3)-O(4) bond length is 2.97 Å. The Ba(3)-O(5) bond length is 2.66 Å. The Ba(3)-O(6) bond length is 2.84 Å. The Ba(3)-O(9) bond length is 2.71 Å. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. The Ba(4)-O(1) bond length is 2.76 Å. The Ba(4)-O(10) bond length is 2.76 Å. The Ba(4)-O(2) bond length is 3.22 Å. The Ba(4)-O(3) bond length is 2.95 Å. The Ba(4)-O(4) bond length is 3.35 Å. The Ba(4)-O(5) bond length is 3.18 Å. The Ba(4)-O(7) bond length is 2.65 Å. The Ba(4)-O(8) bond length is 2.77 Å. In the fifth Ba site, Ba(5) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), one O(8), and one O(9) atom. The Ba(5)-O(1) bond length is 3.32 Å. The Ba(5)-O(2) bond length is 2.74 Å. The Ba(5)-O(3) bond length is 2.57 Å. The Ba(5)-O(6) bond length is 3.01 Å. The Ba(5)-O(7) bond length is 2.84 Å. The Ba(5)-O(8) bond length is 2.84 Å. The Ba(5)-O(9) bond length is 2.81 Å. In the sixth Ba site, Ba(6) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom. The Ba(6)-O(1) bond length is 2.88 Å. The Ba(6)-O(2) bond length is 2.69 Å. The Ba(6)-O(5) bond length is 2.60 Å. The Ba(6)-O(6) bond length is 2.74 Å. The Ba(6)-O(7) bond length is 3.15 Å. The Ba(6)-O(9) bond length is 3.22 Å. Mg(1) is bonded to one O(2), one O(5), one O(6), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Cr(2)O4 tetrahedra and  an edgeedge with one Cr(1)O4 trigonal pyramid. The Mg(1)-O(2) bond length is 1.96 Å. The Mg(1)-O(5) bond length is 2.02 Å. The Mg(1)-O(6) bond length is 1.99 Å. The Mg(1)-O(8) bond length is 2.04 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(4), one O(5), one O(8), and one O(9) atom to form distorted CrO4 trigonal pyramids that share  an edgeedge with one Mg(1)O4 tetrahedra. The Cr(1)-O(4) bond length is 1.87 Å. The Cr(1)-O(5) bond length is 1.93 Å. The Cr(1)-O(8) bond length is 2.00 Å. The Cr(1)-O(9) bond length is 1.90 Å. In the second Cr site, Cr(2) is bonded to one O(10), one O(3), one O(6), and one O(7) atom to form distorted CrO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra. The Cr(2)-O(10) bond length is 1.94 Å. The Cr(2)-O(3) bond length is 1.87 Å. The Cr(2)-O(6) bond length is 1.96 Å. The Cr(2)-O(7) bond length is 1.92 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Ba(6) atom to form a mixture of distorted corner and edge-sharing OBa6 octahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Ba(6), and one Mg(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), and one Cr(1) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(3), one Ba(4), one Ba(6), one Mg(1), and one Cr(1) atom. In the sixth O site, O(6) is bonded to one Ba(3), one Ba(5), one Ba(6), one Mg(1), and one Cr(2) atom to form a mixture of distorted corner and edge-sharing OBa3MgCr square pyramids. The corner-sharing octahedral tilt angles are 58°. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Ba(5), one Ba(6), and one Cr(2) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Mg(1), and one Cr(1) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(5), one Ba(6), and one Cr(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), and one Cr(2) atom.