CaCo2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(13), one O(3), and two equivalent O(1) atoms to form CaO4 tetrahedra that share  a cornercorner with one Ca(6)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Co(6)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-73°. In the second Ca site, Ca(2) is bonded to one O(5), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form CaO6 octahedra that share corners with three equivalent Co(2)O4 tetrahedra, corners with three equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(5)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. In the third Ca site, Ca(3) is bonded to one O(2), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form CaO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. In the fourth Ca site, Ca(4) is bonded to one O(11), one O(15), two equivalent O(10), and two equivalent O(12) atoms to form CaO6 octahedra that share corners with three equivalent Co(5)O4 tetrahedra, corners with three equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(5)O6 octahedra,  an edgeedge with one Ca(6)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. In the fifth Ca site, Ca(5) is bonded to one O(14), one O(6), two equivalent O(12), and two equivalent O(4) atoms to form CaO6 octahedra that share  a cornercorner with one Co(5)O4 tetrahedra,  a cornercorner with one Co(7)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Ca(4)O6 octahedra, and edges with four equivalent Co(4)O6 octahedra. In the sixth Ca site, Ca(6) is bonded to one O(13), one O(18), two equivalent O(10), and two equivalent O(17) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Co(8)O4 tetrahedra, corners with two equivalent Co(5)O4 tetrahedra, corners with two equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, and edges with four equivalent Co(6)O6 octahedra. There are nine inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form CoO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, edges with two equivalent Ca(3)O6 octahedra, and edges with two equivalent Co(1)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2), one O(9), and two equivalent O(4) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra, and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-64°. In the third Co site, Co(3) is bonded to one O(16), one O(3), two equivalent O(1), and two equivalent O(17) atoms to form CoO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(6)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. In the fourth Co site, Co(4) is bonded to one O(11), one O(12), one O(14), one O(4), one O(6), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one Co(5)O4 tetrahedra,  a cornercorner with one Co(7)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Ca(4)O6 octahedra, edges with two equivalent Ca(5)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. In the fifth Co site, Co(5) is bonded to one O(15), one O(6), and two equivalent O(10) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(5)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with three equivalent Ca(4)O6 octahedra, and corners with four equivalent Co(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. In the sixth Co site, Co(6) is bonded to one O(10), one O(13), one O(15), one O(16), one O(17), and one O(18) atom to form CoO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Co(8)O4 tetrahedra, corners with two equivalent Co(5)O4 tetrahedra, corners with two equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, edges with two equivalent Ca(6)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. In the seventh Co site, Co(7) is bonded to one O(14), one O(5), and two equivalent O(7) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(5)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra, and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. In the eighth Co site, Co(8) is bonded to one O(11), one O(18), and two equivalent O(12) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(6)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, corners with two equivalent Co(6)O6 octahedra, corners with three equivalent Ca(4)O6 octahedra, and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-63°. In the ninth Co site, Co(9) is bonded to one O(16), one O(8), and two equivalent O(17) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with four equivalent Co(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(3), one Co(1), and one Co(3) atom to form distorted OCa2Co2 trigonal pyramids that share  a cornercorner with one O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(3)CaCo3 tetrahedra,  a cornercorner with one O(1)Ca2Co2 trigonal pyramid,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(17)CaCo3 trigonal pyramids, corners with two equivalent O(8)CaCo3 trigonal pyramids,  an edgeedge with one O(3)CaCo3 tetrahedra, and  an edgeedge with one O(1)Ca2Co2 trigonal pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(3), one Co(2), and two equivalent Co(1) atoms. In the third O site, O(3) is bonded to one Ca(1), one Co(3), and two equivalent Co(1) atoms to form distorted OCaCo3 tetrahedra that share  a cornercorner with one O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(17)CaCo3 trigonal pyramids, corners with two equivalent O(8)CaCo3 trigonal pyramids, and edges with two equivalent O(1)Ca2Co2 trigonal pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ca(5), one Co(2), and one Co(4) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Co(7), and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ca(5), one Co(5), and two equivalent Co(4) atoms. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ca(3), one Co(1), and one Co(7) atom. In the eighth O site, O(8) is bonded to one Ca(3), one Co(9), and two equivalent Co(1) atoms to form distorted OCaCo3 trigonal pyramids that share corners with two equivalent O(3)CaCo3 tetrahedra,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(17)CaCo3 trigonal pyramids, and corners with four equivalent O(1)Ca2Co2 trigonal pyramids. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Co(2), and two equivalent Co(4) atoms. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Ca(6), one Co(5), and one Co(6) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Co(8), and two equivalent Co(4) atoms. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Ca(5), one Co(4), and one Co(8) atom. In the thirteenth O site, O(13) is bonded to one Ca(1), one Ca(6), and two equivalent Co(6) atoms to form distorted OCa2Co2 tetrahedra that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(16)Co4 trigonal pyramids, and corners with four equivalent O(17)CaCo3 trigonal pyramids. In the fourteenth O site, O(14) is bonded in a rectangular see-saw-like geometry to one Ca(5), one Co(7), and two equivalent Co(4) atoms. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Co(5), and two equivalent Co(6) atoms. In the sixteenth O site, O(16) is bonded to one Co(3), one Co(9), and two equivalent Co(6) atoms to form distorted OCo4 trigonal pyramids that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(8)CaCo3 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(17)CaCo3 trigonal pyramids, and edges with two equivalent O(17)CaCo3 trigonal pyramids. In the seventeenth O site, O(17) is bonded to one Ca(6), one Co(3), one Co(6), and one Co(9) atom to form distorted OCaCo3 trigonal pyramids that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(17)CaCo3 trigonal pyramid,  a cornercorner with one O(8)CaCo3 trigonal pyramid,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids,  an edgeedge with one O(17)CaCo3 trigonal pyramid, and  an edgeedge with one O(16)Co4 trigonal pyramid. In the eighteenth O site, O(18) is bonded in a rectangular see-saw-like geometry to one Ca(6), one Co(8), and two equivalent Co(6) atoms.
CaCo2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(13), one O(3), and two equivalent O(1) atoms to form CaO4 tetrahedra that share  a cornercorner with one Ca(6)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Co(6)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-73°. The Ca(1)-O(13) bond length is 2.18 Å. The Ca(1)-O(3) bond length is 2.26 Å. Both Ca(1)-O(1) bond lengths are 2.14 Å. In the second Ca site, Ca(2) is bonded to one O(5), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form CaO6 octahedra that share corners with three equivalent Co(2)O4 tetrahedra, corners with three equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(5)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The Ca(2)-O(5) bond length is 2.31 Å. The Ca(2)-O(9) bond length is 2.29 Å. Both Ca(2)-O(4) bond lengths are 2.23 Å. Both Ca(2)-O(7) bond lengths are 2.25 Å. In the third Ca site, Ca(3) is bonded to one O(2), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form CaO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. The Ca(3)-O(2) bond length is 2.27 Å. The Ca(3)-O(8) bond length is 2.27 Å. Both Ca(3)-O(1) bond lengths are 2.21 Å. Both Ca(3)-O(7) bond lengths are 2.22 Å. In the fourth Ca site, Ca(4) is bonded to one O(11), one O(15), two equivalent O(10), and two equivalent O(12) atoms to form CaO6 octahedra that share corners with three equivalent Co(5)O4 tetrahedra, corners with three equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(5)O6 octahedra,  an edgeedge with one Ca(6)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. The Ca(4)-O(11) bond length is 2.29 Å. The Ca(4)-O(15) bond length is 2.30 Å. Both Ca(4)-O(10) bond lengths are 2.23 Å. Both Ca(4)-O(12) bond lengths are 2.24 Å. In the fifth Ca site, Ca(5) is bonded to one O(14), one O(6), two equivalent O(12), and two equivalent O(4) atoms to form CaO6 octahedra that share  a cornercorner with one Co(5)O4 tetrahedra,  a cornercorner with one Co(7)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Ca(4)O6 octahedra, and edges with four equivalent Co(4)O6 octahedra. The Ca(5)-O(14) bond length is 2.29 Å. The Ca(5)-O(6) bond length is 2.28 Å. Both Ca(5)-O(12) bond lengths are 2.23 Å. Both Ca(5)-O(4) bond lengths are 2.23 Å. In the sixth Ca site, Ca(6) is bonded to one O(13), one O(18), two equivalent O(10), and two equivalent O(17) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Co(8)O4 tetrahedra, corners with two equivalent Co(5)O4 tetrahedra, corners with two equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, and edges with four equivalent Co(6)O6 octahedra. The Ca(6)-O(13) bond length is 2.24 Å. The Ca(6)-O(18) bond length is 2.24 Å. Both Ca(6)-O(10) bond lengths are 2.25 Å. Both Ca(6)-O(17) bond lengths are 2.24 Å. There are nine inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form CoO6 octahedra that share  a cornercorner with one Co(2)O4 tetrahedra,  a cornercorner with one Co(9)O4 tetrahedra, corners with two equivalent Ca(1)O4 tetrahedra, corners with two equivalent Co(7)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, edges with two equivalent Ca(3)O6 octahedra, and edges with two equivalent Co(1)O6 octahedra. The Co(1)-O(1) bond length is 1.89 Å. The Co(1)-O(2) bond length is 2.02 Å. The Co(1)-O(3) bond length is 1.94 Å. The Co(1)-O(5) bond length is 2.09 Å. The Co(1)-O(7) bond length is 1.94 Å. The Co(1)-O(8) bond length is 2.01 Å. In the second Co site, Co(2) is bonded to one O(2), one O(9), and two equivalent O(4) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra, and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-64°. The Co(2)-O(2) bond length is 1.98 Å. The Co(2)-O(9) bond length is 2.02 Å. Both Co(2)-O(4) bond lengths are 1.85 Å. In the third Co site, Co(3) is bonded to one O(16), one O(3), two equivalent O(1), and two equivalent O(17) atoms to form CoO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(3)O6 octahedra,  an edgeedge with one Ca(6)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. The Co(3)-O(16) bond length is 2.00 Å. The Co(3)-O(3) bond length is 1.94 Å. Both Co(3)-O(1) bond lengths are 1.85 Å. Both Co(3)-O(17) bond lengths are 1.92 Å. In the fourth Co site, Co(4) is bonded to one O(11), one O(12), one O(14), one O(4), one O(6), and one O(9) atom to form CoO6 octahedra that share  a cornercorner with one Co(5)O4 tetrahedra,  a cornercorner with one Co(7)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(8)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra,  an edgeedge with one Ca(4)O6 octahedra, edges with two equivalent Ca(5)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The Co(4)-O(11) bond length is 2.06 Å. The Co(4)-O(12) bond length is 1.93 Å. The Co(4)-O(14) bond length is 2.04 Å. The Co(4)-O(4) bond length is 1.94 Å. The Co(4)-O(6) bond length is 2.03 Å. The Co(4)-O(9) bond length is 2.06 Å. In the fifth Co site, Co(5) is bonded to one O(15), one O(6), and two equivalent O(10) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(5)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with three equivalent Ca(4)O6 octahedra, and corners with four equivalent Co(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. The Co(5)-O(15) bond length is 1.95 Å. The Co(5)-O(6) bond length is 1.97 Å. Both Co(5)-O(10) bond lengths are 1.85 Å. In the sixth Co site, Co(6) is bonded to one O(10), one O(13), one O(15), one O(16), one O(17), and one O(18) atom to form CoO6 octahedra that share  a cornercorner with one Ca(1)O4 tetrahedra,  a cornercorner with one Co(8)O4 tetrahedra, corners with two equivalent Co(5)O4 tetrahedra, corners with two equivalent Co(9)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra,  an edgeedge with one Co(3)O6 octahedra, edges with two equivalent Ca(6)O6 octahedra, and edges with two equivalent Co(6)O6 octahedra. The Co(6)-O(10) bond length is 1.93 Å. The Co(6)-O(13) bond length is 1.93 Å. The Co(6)-O(15) bond length is 2.12 Å. The Co(6)-O(16) bond length is 2.03 Å. The Co(6)-O(17) bond length is 1.96 Å. The Co(6)-O(18) bond length is 2.02 Å. In the seventh Co site, Co(7) is bonded to one O(14), one O(5), and two equivalent O(7) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(5)O6 octahedra, corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra, and corners with four equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-64°. The Co(7)-O(14) bond length is 1.95 Å. The Co(7)-O(5) bond length is 2.00 Å. Both Co(7)-O(7) bond lengths are 1.86 Å. In the eighth Co site, Co(8) is bonded to one O(11), one O(18), and two equivalent O(12) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(6)O6 octahedra, corners with two equivalent Ca(5)O6 octahedra, corners with two equivalent Co(6)O6 octahedra, corners with three equivalent Ca(4)O6 octahedra, and corners with four equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-63°. The Co(8)-O(11) bond length is 2.04 Å. The Co(8)-O(18) bond length is 1.96 Å. Both Co(8)-O(12) bond lengths are 1.86 Å. In the ninth Co site, Co(9) is bonded to one O(16), one O(8), and two equivalent O(17) atoms to form CoO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(6)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with four equivalent Co(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. The Co(9)-O(16) bond length is 2.30 Å. The Co(9)-O(8) bond length is 1.97 Å. Both Co(9)-O(17) bond lengths are 1.98 Å. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(3), one Co(1), and one Co(3) atom to form distorted OCa2Co2 trigonal pyramids that share  a cornercorner with one O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(3)CaCo3 tetrahedra,  a cornercorner with one O(1)Ca2Co2 trigonal pyramid,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(17)CaCo3 trigonal pyramids, corners with two equivalent O(8)CaCo3 trigonal pyramids,  an edgeedge with one O(3)CaCo3 tetrahedra, and  an edgeedge with one O(1)Ca2Co2 trigonal pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(3), one Co(2), and two equivalent Co(1) atoms. In the third O site, O(3) is bonded to one Ca(1), one Co(3), and two equivalent Co(1) atoms to form distorted OCaCo3 tetrahedra that share  a cornercorner with one O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(17)CaCo3 trigonal pyramids, corners with two equivalent O(8)CaCo3 trigonal pyramids, and edges with two equivalent O(1)Ca2Co2 trigonal pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ca(5), one Co(2), and one Co(4) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Co(7), and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ca(5), one Co(5), and two equivalent Co(4) atoms. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ca(3), one Co(1), and one Co(7) atom. In the eighth O site, O(8) is bonded to one Ca(3), one Co(9), and two equivalent Co(1) atoms to form distorted OCaCo3 trigonal pyramids that share corners with two equivalent O(3)CaCo3 tetrahedra,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(17)CaCo3 trigonal pyramids, and corners with four equivalent O(1)Ca2Co2 trigonal pyramids. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Co(2), and two equivalent Co(4) atoms. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Ca(6), one Co(5), and one Co(6) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Co(8), and two equivalent Co(4) atoms. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Ca(5), one Co(4), and one Co(8) atom. In the thirteenth O site, O(13) is bonded to one Ca(1), one Ca(6), and two equivalent Co(6) atoms to form distorted OCa2Co2 tetrahedra that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(16)Co4 trigonal pyramids, and corners with four equivalent O(17)CaCo3 trigonal pyramids. In the fourteenth O site, O(14) is bonded in a rectangular see-saw-like geometry to one Ca(5), one Co(7), and two equivalent Co(4) atoms. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Ca(4), one Co(5), and two equivalent Co(6) atoms. In the sixteenth O site, O(16) is bonded to one Co(3), one Co(9), and two equivalent Co(6) atoms to form distorted OCo4 trigonal pyramids that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(8)CaCo3 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids, corners with two equivalent O(17)CaCo3 trigonal pyramids, and edges with two equivalent O(17)CaCo3 trigonal pyramids. In the seventeenth O site, O(17) is bonded to one Ca(6), one Co(3), one Co(6), and one Co(9) atom to form distorted OCaCo3 trigonal pyramids that share  a cornercorner with one O(3)CaCo3 tetrahedra, corners with two equivalent O(13)Ca2Co2 tetrahedra,  a cornercorner with one O(17)CaCo3 trigonal pyramid,  a cornercorner with one O(8)CaCo3 trigonal pyramid,  a cornercorner with one O(16)Co4 trigonal pyramid, corners with two equivalent O(1)Ca2Co2 trigonal pyramids,  an edgeedge with one O(17)CaCo3 trigonal pyramid, and  an edgeedge with one O(16)Co4 trigonal pyramid. In the eighteenth O site, O(18) is bonded in a rectangular see-saw-like geometry to one Ca(6), one Co(8), and two equivalent Co(6) atoms.