MgLa4Cr2O12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(11), one O(2), one O(4), and one O(8) atom. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(2), one O(3), one O(7), one O(8), and two equivalent O(9) atoms. In the second La site, La(2) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(5), one O(6), one O(9), and two equivalent O(7) atoms. In the third La site, La(3) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. In the fourth La site, La(4) is bonded in a 8-coordinate geometry to one O(11), one O(12), one O(2), one O(5), one O(8), one O(9), and two equivalent O(1) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(10), one O(12), one O(3), and one O(8) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(11), one O(2), one O(4), and one O(6) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one La(1), one La(3), and two equivalent La(4) atoms to form a mixture of distorted corner and edge-sharing OLa4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted water-like geometry to one Mg(1), one La(1), one La(4), and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one La(1), one La(3), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Mg(1), one La(2), one La(3), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one La(2), one La(4), and two equivalent La(3) atoms. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one La(2), one La(3), and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted see-saw-like geometry to one La(1), one La(3), and two equivalent La(2) atoms. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one La(1), one La(4), and one Cr(1) atom. In the ninth O site, O(9) is bonded to one La(2), one La(4), and two equivalent La(1) atoms to form a mixture of distorted corner and edge-sharing OLa4 trigonal pyramids. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one La(2), one La(3), and one Cr(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Mg(1), one La(3), one La(4), and one Cr(2) atom. In the twelfth O site, O(12) is bonded in a single-bond geometry to one La(1), one La(2), one La(4), and one Cr(1) atom.
MgLa4Cr2O12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(11), one O(2), one O(4), and one O(8) atom. The Mg(1)-O(11) bond length is 1.98 Å. The Mg(1)-O(2) bond length is 1.90 Å. The Mg(1)-O(4) bond length is 1.96 Å. The Mg(1)-O(8) bond length is 2.02 Å. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 8-coordinate geometry to one O(1), one O(12), one O(2), one O(3), one O(7), one O(8), and two equivalent O(9) atoms. The La(1)-O(1) bond length is 2.48 Å. The La(1)-O(12) bond length is 2.96 Å. The La(1)-O(2) bond length is 2.81 Å. The La(1)-O(3) bond length is 2.66 Å. The La(1)-O(7) bond length is 2.25 Å. The La(1)-O(8) bond length is 2.74 Å. There is one shorter (2.31 Å) and one longer (2.82 Å) La(1)-O(9) bond length. In the second La site, La(2) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(5), one O(6), one O(9), and two equivalent O(7) atoms. The La(2)-O(10) bond length is 2.79 Å. The La(2)-O(12) bond length is 2.98 Å. The La(2)-O(4) bond length is 2.64 Å. The La(2)-O(5) bond length is 2.38 Å. The La(2)-O(6) bond length is 2.46 Å. The La(2)-O(9) bond length is 2.46 Å. There is one shorter (2.52 Å) and one longer (2.70 Å) La(2)-O(7) bond length. In the third La site, La(3) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. The La(3)-O(1) bond length is 2.51 Å. The La(3)-O(10) bond length is 2.96 Å. The La(3)-O(11) bond length is 2.88 Å. The La(3)-O(3) bond length is 2.74 Å. The La(3)-O(4) bond length is 3.03 Å. The La(3)-O(6) bond length is 2.50 Å. The La(3)-O(7) bond length is 2.40 Å. There is one shorter (2.43 Å) and one longer (2.75 Å) La(3)-O(5) bond length. In the fourth La site, La(4) is bonded in a 8-coordinate geometry to one O(11), one O(12), one O(2), one O(5), one O(8), one O(9), and two equivalent O(1) atoms. The La(4)-O(11) bond length is 2.54 Å. The La(4)-O(12) bond length is 2.88 Å. The La(4)-O(2) bond length is 2.94 Å. The La(4)-O(5) bond length is 2.42 Å. The La(4)-O(8) bond length is 3.24 Å. The La(4)-O(9) bond length is 2.34 Å. There is one shorter (2.46 Å) and one longer (2.57 Å) La(4)-O(1) bond length. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(10), one O(12), one O(3), and one O(8) atom. The Cr(1)-O(10) bond length is 1.65 Å. The Cr(1)-O(12) bond length is 1.65 Å. The Cr(1)-O(3) bond length is 1.66 Å. The Cr(1)-O(8) bond length is 1.71 Å. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(11), one O(2), one O(4), and one O(6) atom. The Cr(2)-O(11) bond length is 1.83 Å. The Cr(2)-O(2) bond length is 1.81 Å. The Cr(2)-O(4) bond length is 1.81 Å. The Cr(2)-O(6) bond length is 1.76 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one La(1), one La(3), and two equivalent La(4) atoms to form a mixture of distorted corner and edge-sharing OLa4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted water-like geometry to one Mg(1), one La(1), one La(4), and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one La(1), one La(3), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Mg(1), one La(2), one La(3), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one La(2), one La(4), and two equivalent La(3) atoms. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one La(2), one La(3), and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted see-saw-like geometry to one La(1), one La(3), and two equivalent La(2) atoms. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one La(1), one La(4), and one Cr(1) atom. In the ninth O site, O(9) is bonded to one La(2), one La(4), and two equivalent La(1) atoms to form a mixture of distorted corner and edge-sharing OLa4 trigonal pyramids. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one La(2), one La(3), and one Cr(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Mg(1), one La(3), one La(4), and one Cr(2) atom. In the twelfth O site, O(12) is bonded in a single-bond geometry to one La(1), one La(2), one La(4), and one Cr(1) atom.