CaEuTi4O12 crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(5) atoms to form distorted CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. Eu(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. Ti(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-16°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Ti(1) atoms. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Ca(1) and two equivalent Ti(1) atoms.
CaEuTi4O12 crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(5) atoms to form distorted CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. Both Ca(1)-O(2) bond lengths are 2.50 Å. Both Ca(1)-O(3) bond lengths are 2.75 Å. All Ca(1)-O(1) bond lengths are 2.93 Å. There are two shorter (2.54 Å) and two longer (2.95 Å) Ca(1)-O(5) bond lengths. Eu(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ti(1)O6 octahedra. Both Eu(1)-O(2) bond lengths are 3.06 Å. Both Eu(1)-O(3) bond lengths are 2.69 Å. All Eu(1)-O(1) bond lengths are 2.56 Å. There are two shorter (2.63 Å) and two longer (2.86 Å) Eu(1)-O(4) bond lengths. Ti(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-16°. The Ti(1)-O(2) bond length is 1.94 Å. The Ti(1)-O(3) bond length is 1.97 Å. The Ti(1)-O(4) bond length is 1.97 Å. The Ti(1)-O(5) bond length is 1.94 Å. Both Ti(1)-O(1) bond lengths are 1.95 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Eu(1), and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Ti(1) atoms. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to two equivalent Ca(1) and two equivalent Ti(1) atoms.