MgCu2O4 crystallizes in the triclinic P1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to one O(6), one O(8), two equivalent O(11), two equivalent O(14), and two equivalent O(3) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(12), two equivalent O(13), and two equivalent O(4) atoms. In the third Mg site, Mg(3) is bonded in a 8-coordinate geometry to one O(6), one O(8), two equivalent O(1), two equivalent O(15), and two equivalent O(9) atoms. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(10), two equivalent O(16), and two equivalent O(2) atoms. There are eight inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(14), one O(9), two equivalent O(10), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the second Cu site, Cu(2) is bonded to one O(12), one O(16), two equivalent O(11), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. In the third Cu site, Cu(3) is bonded to one O(11), one O(15), two equivalent O(12), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the fourth Cu site, Cu(4) is bonded to one O(10), one O(13), two equivalent O(7), and two equivalent O(9) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. In the fifth Cu site, Cu(5) is bonded to one O(4), one O(8), two equivalent O(15), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the sixth Cu site, Cu(6) is bonded to one O(3), one O(7), two equivalent O(16), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. In the seventh Cu site, Cu(7) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(14) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. In the eighth Cu site, Cu(8) is bonded to one O(1), one O(5), two equivalent O(13), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(3), one Cu(8), and two equivalent Cu(7) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(4), one Cu(7), and two equivalent Cu(8) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Cu(6), and two equivalent Cu(5) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Mg(2), one Cu(5), and two equivalent Cu(6) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), one Cu(8), and two equivalent Cu(2) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the sixth O site, O(6) is bonded to one Mg(1), one Mg(3), one Cu(7), and two equivalent Cu(3) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the seventh O site, O(7) is bonded to one Mg(2), one Mg(4), one Cu(6), and two equivalent Cu(4) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Mg(1), one Mg(3), one Cu(5), and two equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the ninth O site, O(9) is bonded to two equivalent Mg(3), one Cu(1), and two equivalent Cu(4) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the tenth O site, O(10) is bonded to two equivalent Mg(4), one Cu(4), and two equivalent Cu(1) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the eleventh O site, O(11) is bonded to two equivalent Mg(1), one Cu(3), and two equivalent Cu(2) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the twelfth O site, O(12) is bonded to two equivalent Mg(2), one Cu(2), and two equivalent Cu(3) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the thirteenth O site, O(13) is bonded to two equivalent Mg(2), one Cu(4), and two equivalent Cu(8) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fourteenth O site, O(14) is bonded to two equivalent Mg(1), one Cu(1), and two equivalent Cu(7) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fifteenth O site, O(15) is bonded to two equivalent Mg(3), one Cu(3), and two equivalent Cu(5) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the sixteenth O site, O(16) is bonded to two equivalent Mg(4), one Cu(2), and two equivalent Cu(6) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids.
MgCu2O4 crystallizes in the triclinic P1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 8-coordinate geometry to one O(6), one O(8), two equivalent O(11), two equivalent O(14), and two equivalent O(3) atoms. The Mg(1)-O(6) bond length is 2.38 Å. The Mg(1)-O(8) bond length is 2.38 Å. There is one shorter (2.19 Å) and one longer (2.21 Å) Mg(1)-O(11) bond length. There is one shorter (2.23 Å) and one longer (2.24 Å) Mg(1)-O(14) bond length. There is one shorter (2.23 Å) and one longer (2.24 Å) Mg(1)-O(3) bond length. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(12), two equivalent O(13), and two equivalent O(4) atoms. The Mg(2)-O(5) bond length is 2.42 Å. The Mg(2)-O(7) bond length is 2.40 Å. There is one shorter (2.18 Å) and one longer (2.21 Å) Mg(2)-O(12) bond length. There is one shorter (2.20 Å) and one longer (2.23 Å) Mg(2)-O(13) bond length. There is one shorter (2.20 Å) and one longer (2.24 Å) Mg(2)-O(4) bond length. In the third Mg site, Mg(3) is bonded in a 8-coordinate geometry to one O(6), one O(8), two equivalent O(1), two equivalent O(15), and two equivalent O(9) atoms. The Mg(3)-O(6) bond length is 2.40 Å. The Mg(3)-O(8) bond length is 2.43 Å. There is one shorter (2.20 Å) and one longer (2.24 Å) Mg(3)-O(1) bond length. There is one shorter (2.22 Å) and one longer (2.25 Å) Mg(3)-O(15) bond length. Both Mg(3)-O(9) bond lengths are 2.19 Å. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(10), two equivalent O(16), and two equivalent O(2) atoms. The Mg(4)-O(5) bond length is 2.35 Å. The Mg(4)-O(7) bond length is 2.40 Å. There is one shorter (2.20 Å) and one longer (2.24 Å) Mg(4)-O(10) bond length. There is one shorter (2.22 Å) and one longer (2.24 Å) Mg(4)-O(16) bond length. Both Mg(4)-O(2) bond lengths are 2.22 Å. There are eight inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(14), one O(9), two equivalent O(10), and two equivalent O(8) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. The Cu(1)-O(14) bond length is 1.94 Å. The Cu(1)-O(9) bond length is 1.96 Å. There is one shorter (2.04 Å) and one longer (2.06 Å) Cu(1)-O(10) bond length. There is one shorter (1.95 Å) and one longer (1.96 Å) Cu(1)-O(8) bond length. In the second Cu site, Cu(2) is bonded to one O(12), one O(16), two equivalent O(11), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. The Cu(2)-O(12) bond length is 1.95 Å. The Cu(2)-O(16) bond length is 1.94 Å. There is one shorter (2.04 Å) and one longer (2.05 Å) Cu(2)-O(11) bond length. Both Cu(2)-O(5) bond lengths are 1.95 Å. In the third Cu site, Cu(3) is bonded to one O(11), one O(15), two equivalent O(12), and two equivalent O(6) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. The Cu(3)-O(11) bond length is 1.95 Å. The Cu(3)-O(15) bond length is 1.94 Å. Both Cu(3)-O(12) bond lengths are 2.06 Å. There is one shorter (1.95 Å) and one longer (1.96 Å) Cu(3)-O(6) bond length. In the fourth Cu site, Cu(4) is bonded to one O(10), one O(13), two equivalent O(7), and two equivalent O(9) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. The Cu(4)-O(10) bond length is 1.95 Å. The Cu(4)-O(13) bond length is 1.94 Å. There is one shorter (1.94 Å) and one longer (1.95 Å) Cu(4)-O(7) bond length. There is one shorter (2.05 Å) and one longer (2.06 Å) Cu(4)-O(9) bond length. In the fifth Cu site, Cu(5) is bonded to one O(4), one O(8), two equivalent O(15), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. The Cu(5)-O(4) bond length is 1.98 Å. The Cu(5)-O(8) bond length is 1.89 Å. Both Cu(5)-O(15) bond lengths are 2.07 Å. There is one shorter (2.04 Å) and one longer (2.05 Å) Cu(5)-O(3) bond length. In the sixth Cu site, Cu(6) is bonded to one O(3), one O(7), two equivalent O(16), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. The Cu(6)-O(3) bond length is 1.97 Å. The Cu(6)-O(7) bond length is 1.89 Å. There is one shorter (2.05 Å) and one longer (2.06 Å) Cu(6)-O(16) bond length. There is one shorter (2.04 Å) and one longer (2.06 Å) Cu(6)-O(4) bond length. In the seventh Cu site, Cu(7) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(14) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-63°. The Cu(7)-O(2) bond length is 1.97 Å. The Cu(7)-O(6) bond length is 1.89 Å. There is one shorter (2.04 Å) and one longer (2.05 Å) Cu(7)-O(1) bond length. There is one shorter (2.05 Å) and one longer (2.06 Å) Cu(7)-O(14) bond length. In the eighth Cu site, Cu(8) is bonded to one O(1), one O(5), two equivalent O(13), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. The Cu(8)-O(1) bond length is 1.97 Å. The Cu(8)-O(5) bond length is 1.90 Å. Both Cu(8)-O(13) bond lengths are 2.07 Å. There is one shorter (2.05 Å) and one longer (2.06 Å) Cu(8)-O(2) bond length. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(3), one Cu(8), and two equivalent Cu(7) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(4), one Cu(7), and two equivalent Cu(8) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Cu(6), and two equivalent Cu(5) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Mg(2), one Cu(5), and two equivalent Cu(6) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), one Cu(8), and two equivalent Cu(2) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the sixth O site, O(6) is bonded to one Mg(1), one Mg(3), one Cu(7), and two equivalent Cu(3) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the seventh O site, O(7) is bonded to one Mg(2), one Mg(4), one Cu(6), and two equivalent Cu(4) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Mg(1), one Mg(3), one Cu(5), and two equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the ninth O site, O(9) is bonded to two equivalent Mg(3), one Cu(1), and two equivalent Cu(4) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the tenth O site, O(10) is bonded to two equivalent Mg(4), one Cu(4), and two equivalent Cu(1) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the eleventh O site, O(11) is bonded to two equivalent Mg(1), one Cu(3), and two equivalent Cu(2) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the twelfth O site, O(12) is bonded to two equivalent Mg(2), one Cu(2), and two equivalent Cu(3) atoms to form a mixture of edge and corner-sharing OMg2Cu3 square pyramids. In the thirteenth O site, O(13) is bonded to two equivalent Mg(2), one Cu(4), and two equivalent Cu(8) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fourteenth O site, O(14) is bonded to two equivalent Mg(1), one Cu(1), and two equivalent Cu(7) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the fifteenth O site, O(15) is bonded to two equivalent Mg(3), one Cu(3), and two equivalent Cu(5) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids. In the sixteenth O site, O(16) is bonded to two equivalent Mg(4), one Cu(2), and two equivalent Cu(6) atoms to form a mixture of distorted edge and corner-sharing OMg2Cu3 trigonal bipyramids.