CaTiO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing CaO6 octahedra. In the second Ca site, Ca(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of distorted edge, face, and corner-sharing CaO6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 20-63°. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the second Ti site, Ti(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1), one Ti(2), and two equivalent Ti(1) atoms to form OCa3Ti3 octahedra that share corners with two equivalent O(3)Ca4Ti square pyramids, corners with four equivalent O(2)Ca2Ti3 square pyramids,  a cornercorner with one O(4)Ca3Ti2 trigonal bipyramid, edges with four equivalent O(1)Ca3Ti3 octahedra, edges with three equivalent O(3)Ca4Ti square pyramids, and edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(2), one Ti(1), and two equivalent Ti(2) atoms to form OCa2Ti3 square pyramids that share corners with four equivalent O(1)Ca3Ti3 octahedra, corners with two equivalent O(3)Ca4Ti square pyramids, corners with four equivalent O(4)Ca3Ti2 trigonal bipyramids, edges with two equivalent O(2)Ca2Ti3 square pyramids, edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids, and  a faceface with one O(3)Ca4Ti square pyramid. The corner-sharing octahedral tilt angles range from 46-50°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Ti(1) atom to form distorted OCa4Ti square pyramids that share corners with two equivalent O(1)Ca3Ti3 octahedra, corners with two equivalent O(2)Ca2Ti3 square pyramids, corners with four equivalent O(4)Ca3Ti2 trigonal bipyramids, edges with three equivalent O(1)Ca3Ti3 octahedra, edges with two equivalent O(3)Ca4Ti square pyramids,  an edgeedge with one O(4)Ca3Ti2 trigonal bipyramid, and  a faceface with one O(2)Ca2Ti3 square pyramid. The corner-sharing octahedral tilt angles are 10°. In the fourth O site, O(4) is bonded to one Ca(1), two equivalent Ca(2), and two equivalent Ti(2) atoms to form distorted OCa3Ti2 trigonal bipyramids that share  a cornercorner with one O(1)Ca3Ti3 octahedra, corners with four equivalent O(2)Ca2Ti3 square pyramids, corners with four equivalent O(3)Ca4Ti square pyramids, edges with two equivalent O(1)Ca3Ti3 octahedra,  an edgeedge with one O(3)Ca4Ti square pyramid, edges with two equivalent O(2)Ca2Ti3 square pyramids, and edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°.
CaTiO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing CaO6 octahedra. The Ca(1)-O(4) bond length is 2.22 Å. Both Ca(1)-O(3) bond lengths are 2.24 Å. There are a spread of Ca(1)-O(1) bond distances ranging from 2.38-2.67 Å. In the second Ca site, Ca(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of distorted edge, face, and corner-sharing CaO6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 20-63°. There is one shorter (2.35 Å) and one longer (2.36 Å) Ca(2)-O(2) bond length. There is one shorter (2.35 Å) and one longer (2.36 Å) Ca(2)-O(3) bond length. There is one shorter (2.38 Å) and one longer (2.42 Å) Ca(2)-O(4) bond length. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. The Ti(1)-O(2) bond length is 2.03 Å. The Ti(1)-O(3) bond length is 2.11 Å. There is one shorter (2.17 Å) and one longer (2.18 Å) Ti(1)-O(1) bond length. In the second Ti site, Ti(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(4) atoms. The Ti(2)-O(1) bond length is 2.11 Å. There is one shorter (2.07 Å) and one longer (2.08 Å) Ti(2)-O(2) bond length. There is one shorter (2.11 Å) and one longer (2.29 Å) Ti(2)-O(4) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1), one Ti(2), and two equivalent Ti(1) atoms to form OCa3Ti3 octahedra that share corners with two equivalent O(3)Ca4Ti square pyramids, corners with four equivalent O(2)Ca2Ti3 square pyramids,  a cornercorner with one O(4)Ca3Ti2 trigonal bipyramid, edges with four equivalent O(1)Ca3Ti3 octahedra, edges with three equivalent O(3)Ca4Ti square pyramids, and edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(2), one Ti(1), and two equivalent Ti(2) atoms to form OCa2Ti3 square pyramids that share corners with four equivalent O(1)Ca3Ti3 octahedra, corners with two equivalent O(3)Ca4Ti square pyramids, corners with four equivalent O(4)Ca3Ti2 trigonal bipyramids, edges with two equivalent O(2)Ca2Ti3 square pyramids, edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids, and  a faceface with one O(3)Ca4Ti square pyramid. The corner-sharing octahedral tilt angles range from 46-50°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Ti(1) atom to form distorted OCa4Ti square pyramids that share corners with two equivalent O(1)Ca3Ti3 octahedra, corners with two equivalent O(2)Ca2Ti3 square pyramids, corners with four equivalent O(4)Ca3Ti2 trigonal bipyramids, edges with three equivalent O(1)Ca3Ti3 octahedra, edges with two equivalent O(3)Ca4Ti square pyramids,  an edgeedge with one O(4)Ca3Ti2 trigonal bipyramid, and  a faceface with one O(2)Ca2Ti3 square pyramid. The corner-sharing octahedral tilt angles are 10°. In the fourth O site, O(4) is bonded to one Ca(1), two equivalent Ca(2), and two equivalent Ti(2) atoms to form distorted OCa3Ti2 trigonal bipyramids that share  a cornercorner with one O(1)Ca3Ti3 octahedra, corners with four equivalent O(2)Ca2Ti3 square pyramids, corners with four equivalent O(3)Ca4Ti square pyramids, edges with two equivalent O(1)Ca3Ti3 octahedra,  an edgeedge with one O(3)Ca4Ti square pyramid, edges with two equivalent O(2)Ca2Ti3 square pyramids, and edges with two equivalent O(4)Ca3Ti2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°.