CaTi2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3) and three equivalent O(4) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(2)O6 octahedra and corners with nine equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-73°. In the second Ca site, Ca(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Ti(1)O4 tetrahedra, and edges with six equivalent Ti(2)O6 octahedra. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2) and three equivalent O(1) atoms to form TiO4 tetrahedra that share corners with three equivalent Ca(2)O6 octahedra and corners with nine equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Ti(1)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, and edges with four equivalent Ti(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ti(1), and two equivalent Ti(2) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ti(1) and three equivalent Ti(2) atoms. In the third O site, O(3) is bonded to one Ca(1) and three equivalent Ti(2) atoms to form a mixture of distorted edge and corner-sharing OCaTi3 trigonal pyramids. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Ti(2) atoms to form distorted OCa2Ti2 trigonal pyramids that share  a cornercorner with one O(3)CaTi3 trigonal pyramid, corners with two equivalent O(4)Ca2Ti2 trigonal pyramids,  an edgeedge with one O(3)CaTi3 trigonal pyramid, and edges with two equivalent O(4)Ca2Ti2 trigonal pyramids.
CaTi2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3) and three equivalent O(4) atoms to form CaO4 tetrahedra that share corners with three equivalent Ca(2)O6 octahedra and corners with nine equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-73°. The Ca(1)-O(3) bond length is 2.25 Å. All Ca(1)-O(4) bond lengths are 2.18 Å. In the second Ca site, Ca(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form CaO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Ti(1)O4 tetrahedra, and edges with six equivalent Ti(2)O6 octahedra. All Ca(2)-O(1) bond lengths are 2.32 Å. All Ca(2)-O(4) bond lengths are 2.26 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2) and three equivalent O(1) atoms to form TiO4 tetrahedra that share corners with three equivalent Ca(2)O6 octahedra and corners with nine equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. The Ti(1)-O(2) bond length is 1.94 Å. All Ti(1)-O(1) bond lengths are 1.88 Å. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Ca(1)O4 tetrahedra, corners with three equivalent Ti(1)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, and edges with four equivalent Ti(2)O6 octahedra. The Ti(2)-O(2) bond length is 2.28 Å. The Ti(2)-O(3) bond length is 2.12 Å. Both Ti(2)-O(1) bond lengths are 2.15 Å. Both Ti(2)-O(4) bond lengths are 2.00 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Ti(1), and two equivalent Ti(2) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ti(1) and three equivalent Ti(2) atoms. In the third O site, O(3) is bonded to one Ca(1) and three equivalent Ti(2) atoms to form a mixture of distorted edge and corner-sharing OCaTi3 trigonal pyramids. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Ti(2) atoms to form distorted OCa2Ti2 trigonal pyramids that share  a cornercorner with one O(3)CaTi3 trigonal pyramid, corners with two equivalent O(4)Ca2Ti2 trigonal pyramids,  an edgeedge with one O(3)CaTi3 trigonal pyramid, and edges with two equivalent O(4)Ca2Ti2 trigonal pyramids.