Ca(CuO2)2 is Spinel-like structured and crystallizes in the trigonal P3m1 space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(9) and three equivalent O(1) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(5)O6 octahedra, corners with three equivalent Cu(5)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-69°. In the second Ca site, Ca(2) is bonded to one O(2) and three equivalent O(3) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(3)O6 octahedra, corners with three equivalent Cu(1)O6 octahedra, and corners with six equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-72°. In the third Ca site, Ca(3) is bonded to three equivalent O(3) and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with three equivalent Ca(2)O4 tetrahedra, corners with three equivalent Cu(4)O4 tetrahedra, edges with three equivalent Cu(1)O6 octahedra, and edges with three equivalent Cu(2)O6 octahedra. In the fourth Ca site, Ca(4) is bonded to one O(5) and three equivalent O(7) atoms to form distorted CaO4 trigonal pyramids that share corners with three equivalent Cu(2)O6 octahedra, corners with three equivalent Cu(3)O6 octahedra, and corners with six equivalent Cu(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-74°. In the fifth Ca site, Ca(5) is bonded to three equivalent O(1) and three equivalent O(11) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Cu(6)O4 tetrahedra, edges with three equivalent Cu(1)O6 octahedra, and edges with three equivalent Cu(5)O6 octahedra. In the sixth Ca site, Ca(6) is bonded to one O(12) and three equivalent O(8) atoms to form CaO4 tetrahedra that share corners with three equivalent Cu(3)O6 octahedra, corners with three equivalent Cu(5)O6 octahedra, and corners with six equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles are 64°. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(4) atoms to form CuO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Cu(6)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Cu(4)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(5)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. In the second Cu site, Cu(2) is bonded to one O(10), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted CuO6 octahedra that share  a cornercorner with one Cu(4)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  a cornercorner with one Ca(4)O4 trigonal pyramid,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Cu(3)O6 octahedra, and edges with four equivalent Cu(2)O6 octahedra. In the third Cu site, Cu(3) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form CuO6 octahedra that share corners with three equivalent Ca(6)O4 tetrahedra, corners with three equivalent Ca(4)O4 trigonal pyramids, edges with three equivalent Cu(2)O6 octahedra, and edges with three equivalent Cu(5)O6 octahedra. In the fourth Cu site, Cu(4) is bonded to one O(10) and three equivalent O(4) atoms to form CuO4 tetrahedra that share corners with three equivalent Ca(3)O6 octahedra, corners with three equivalent Cu(2)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-66°. In the fifth Cu site, Cu(5) is bonded to one O(12), one O(9), two equivalent O(11), and two equivalent O(7) atoms to form CuO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Cu(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 trigonal pyramids,  an edgeedge with one Ca(5)O6 octahedra,  an edgeedge with one Cu(3)O6 octahedra, and edges with four equivalent Cu(5)O6 octahedra. In the sixth Cu site, Cu(6) is bonded to one O(6) and three equivalent O(11) atoms to form CuO4 tetrahedra that share corners with three equivalent Ca(5)O6 octahedra, corners with three equivalent Cu(1)O6 octahedra, and corners with six equivalent Cu(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(5), and two equivalent Cu(1) atoms to form distorted OCa2Cu2 tetrahedra that share corners with two equivalent O(1)Ca2Cu2 tetrahedra,  a cornercorner with one O(9)CaCu3 trigonal pyramid, corners with four equivalent O(4)CaCu3 trigonal pyramids, and edges with two equivalent O(1)Ca2Cu2 tetrahedra. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(2) and three equivalent Cu(1) atoms. In the third O site, O(3) is bonded to one Ca(2), one Ca(3), and two equivalent Cu(2) atoms to form distorted OCa2Cu2 trigonal pyramids that share corners with four equivalent O(8)CaCu3 tetrahedra, corners with two equivalent O(3)Ca2Cu2 trigonal pyramids, corners with three equivalent O(4)CaCu3 trigonal pyramids, and edges with two equivalent O(3)Ca2Cu2 trigonal pyramids. In the fourth O site, O(4) is bonded to one Ca(3), one Cu(4), and two equivalent Cu(1) atoms to form distorted OCaCu3 trigonal pyramids that share corners with four equivalent O(1)Ca2Cu2 tetrahedra, corners with two equivalent O(4)CaCu3 trigonal pyramids, corners with three equivalent O(3)Ca2Cu2 trigonal pyramids, and edges with two equivalent O(4)CaCu3 trigonal pyramids. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Ca(4) and three equivalent Cu(2) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Cu(6) and three equivalent Cu(1) atoms. In the seventh O site, O(7) is bonded to one Ca(4), one Cu(3), and two equivalent Cu(5) atoms to form a mixture of edge and corner-sharing OCaCu3 tetrahedra. In the eighth O site, O(8) is bonded to one Ca(6), one Cu(3), and two equivalent Cu(2) atoms to form OCaCu3 tetrahedra that share  a cornercorner with one O(12)CaCu3 tetrahedra, corners with two equivalent O(8)CaCu3 tetrahedra, corners with three equivalent O(7)CaCu3 tetrahedra, corners with four equivalent O(3)Ca2Cu2 trigonal pyramids, and edges with two equivalent O(8)CaCu3 tetrahedra. In the ninth O site, O(9) is bonded to one Ca(1) and three equivalent Cu(5) atoms to form distorted OCaCu3 trigonal pyramids that share corners with three equivalent O(1)Ca2Cu2 tetrahedra, corners with three equivalent O(12)CaCu3 tetrahedra, and edges with three equivalent O(7)CaCu3 tetrahedra. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Cu(4) and three equivalent Cu(2) atoms. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(5), one Cu(6), and two equivalent Cu(5) atoms. In the twelfth O site, O(12) is bonded to one Ca(6) and three equivalent Cu(5) atoms to form corner-sharing OCaCu3 tetrahedra.
Ca(CuO2)2 is Spinel-like structured and crystallizes in the trigonal P3m1 space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(9) and three equivalent O(1) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(5)O6 octahedra, corners with three equivalent Cu(5)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-69°. The Ca(1)-O(9) bond length is 2.33 Å. All Ca(1)-O(1) bond lengths are 2.20 Å. In the second Ca site, Ca(2) is bonded to one O(2) and three equivalent O(3) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(3)O6 octahedra, corners with three equivalent Cu(1)O6 octahedra, and corners with six equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-72°. The Ca(2)-O(2) bond length is 2.18 Å. All Ca(2)-O(3) bond lengths are 2.21 Å. In the third Ca site, Ca(3) is bonded to three equivalent O(3) and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with three equivalent Ca(2)O4 tetrahedra, corners with three equivalent Cu(4)O4 tetrahedra, edges with three equivalent Cu(1)O6 octahedra, and edges with three equivalent Cu(2)O6 octahedra. All Ca(3)-O(3) bond lengths are 2.33 Å. All Ca(3)-O(4) bond lengths are 2.35 Å. In the fourth Ca site, Ca(4) is bonded to one O(5) and three equivalent O(7) atoms to form distorted CaO4 trigonal pyramids that share corners with three equivalent Cu(2)O6 octahedra, corners with three equivalent Cu(3)O6 octahedra, and corners with six equivalent Cu(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-74°. The Ca(4)-O(5) bond length is 2.34 Å. All Ca(4)-O(7) bond lengths are 2.15 Å. In the fifth Ca site, Ca(5) is bonded to three equivalent O(1) and three equivalent O(11) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Cu(6)O4 tetrahedra, edges with three equivalent Cu(1)O6 octahedra, and edges with three equivalent Cu(5)O6 octahedra. All Ca(5)-O(1) bond lengths are 2.30 Å. All Ca(5)-O(11) bond lengths are 2.35 Å. In the sixth Ca site, Ca(6) is bonded to one O(12) and three equivalent O(8) atoms to form CaO4 tetrahedra that share corners with three equivalent Cu(3)O6 octahedra, corners with three equivalent Cu(5)O6 octahedra, and corners with six equivalent Cu(2)O6 octahedra. The corner-sharing octahedral tilt angles are 64°. The Ca(6)-O(12) bond length is 2.26 Å. All Ca(6)-O(8) bond lengths are 2.26 Å. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(4) atoms to form CuO6 octahedra that share  a cornercorner with one Ca(2)O4 tetrahedra,  a cornercorner with one Cu(6)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Cu(4)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(5)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. The Cu(1)-O(2) bond length is 2.15 Å. The Cu(1)-O(6) bond length is 2.27 Å. Both Cu(1)-O(1) bond lengths are 1.92 Å. Both Cu(1)-O(4) bond lengths are 1.98 Å. In the second Cu site, Cu(2) is bonded to one O(10), one O(5), two equivalent O(3), and two equivalent O(8) atoms to form distorted CuO6 octahedra that share  a cornercorner with one Cu(4)O4 tetrahedra, corners with two equivalent Ca(2)O4 tetrahedra, corners with two equivalent Ca(6)O4 tetrahedra,  a cornercorner with one Ca(4)O4 trigonal pyramid,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Cu(3)O6 octahedra, and edges with four equivalent Cu(2)O6 octahedra. The Cu(2)-O(10) bond length is 2.50 Å. The Cu(2)-O(5) bond length is 2.20 Å. Both Cu(2)-O(3) bond lengths are 1.91 Å. Both Cu(2)-O(8) bond lengths are 1.93 Å. In the third Cu site, Cu(3) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form CuO6 octahedra that share corners with three equivalent Ca(6)O4 tetrahedra, corners with three equivalent Ca(4)O4 trigonal pyramids, edges with three equivalent Cu(2)O6 octahedra, and edges with three equivalent Cu(5)O6 octahedra. All Cu(3)-O(7) bond lengths are 1.94 Å. All Cu(3)-O(8) bond lengths are 2.04 Å. In the fourth Cu site, Cu(4) is bonded to one O(10) and three equivalent O(4) atoms to form CuO4 tetrahedra that share corners with three equivalent Ca(3)O6 octahedra, corners with three equivalent Cu(2)O6 octahedra, and corners with six equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-66°. The Cu(4)-O(10) bond length is 1.86 Å. All Cu(4)-O(4) bond lengths are 2.06 Å. In the fifth Cu site, Cu(5) is bonded to one O(12), one O(9), two equivalent O(11), and two equivalent O(7) atoms to form CuO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Ca(6)O4 tetrahedra, corners with two equivalent Cu(6)O4 tetrahedra, corners with two equivalent Ca(4)O4 trigonal pyramids,  an edgeedge with one Ca(5)O6 octahedra,  an edgeedge with one Cu(3)O6 octahedra, and edges with four equivalent Cu(5)O6 octahedra. The Cu(5)-O(12) bond length is 2.05 Å. The Cu(5)-O(9) bond length is 2.04 Å. Both Cu(5)-O(11) bond lengths are 2.08 Å. Both Cu(5)-O(7) bond lengths are 2.03 Å. In the sixth Cu site, Cu(6) is bonded to one O(6) and three equivalent O(11) atoms to form CuO4 tetrahedra that share corners with three equivalent Ca(5)O6 octahedra, corners with three equivalent Cu(1)O6 octahedra, and corners with six equivalent Cu(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. The Cu(6)-O(6) bond length is 1.88 Å. All Cu(6)-O(11) bond lengths are 1.98 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(5), and two equivalent Cu(1) atoms to form distorted OCa2Cu2 tetrahedra that share corners with two equivalent O(1)Ca2Cu2 tetrahedra,  a cornercorner with one O(9)CaCu3 trigonal pyramid, corners with four equivalent O(4)CaCu3 trigonal pyramids, and edges with two equivalent O(1)Ca2Cu2 tetrahedra. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(2) and three equivalent Cu(1) atoms. In the third O site, O(3) is bonded to one Ca(2), one Ca(3), and two equivalent Cu(2) atoms to form distorted OCa2Cu2 trigonal pyramids that share corners with four equivalent O(8)CaCu3 tetrahedra, corners with two equivalent O(3)Ca2Cu2 trigonal pyramids, corners with three equivalent O(4)CaCu3 trigonal pyramids, and edges with two equivalent O(3)Ca2Cu2 trigonal pyramids. In the fourth O site, O(4) is bonded to one Ca(3), one Cu(4), and two equivalent Cu(1) atoms to form distorted OCaCu3 trigonal pyramids that share corners with four equivalent O(1)Ca2Cu2 tetrahedra, corners with two equivalent O(4)CaCu3 trigonal pyramids, corners with three equivalent O(3)Ca2Cu2 trigonal pyramids, and edges with two equivalent O(4)CaCu3 trigonal pyramids. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Ca(4) and three equivalent Cu(2) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Cu(6) and three equivalent Cu(1) atoms. In the seventh O site, O(7) is bonded to one Ca(4), one Cu(3), and two equivalent Cu(5) atoms to form a mixture of edge and corner-sharing OCaCu3 tetrahedra. In the eighth O site, O(8) is bonded to one Ca(6), one Cu(3), and two equivalent Cu(2) atoms to form OCaCu3 tetrahedra that share  a cornercorner with one O(12)CaCu3 tetrahedra, corners with two equivalent O(8)CaCu3 tetrahedra, corners with three equivalent O(7)CaCu3 tetrahedra, corners with four equivalent O(3)Ca2Cu2 trigonal pyramids, and edges with two equivalent O(8)CaCu3 tetrahedra. In the ninth O site, O(9) is bonded to one Ca(1) and three equivalent Cu(5) atoms to form distorted OCaCu3 trigonal pyramids that share corners with three equivalent O(1)Ca2Cu2 tetrahedra, corners with three equivalent O(12)CaCu3 tetrahedra, and edges with three equivalent O(7)CaCu3 tetrahedra. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Cu(4) and three equivalent Cu(2) atoms. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(5), one Cu(6), and two equivalent Cu(5) atoms. In the twelfth O site, O(12) is bonded to one Ca(6) and three equivalent Cu(5) atoms to form corner-sharing OCaCu3 tetrahedra.