Ba2ZrO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. Zr(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Ba(1) and two equivalent Zr(1) atoms to form distorted OBa4Zr2 octahedra that share corners with two equivalent O(2)Ba4Zr2 octahedra, corners with twelve equivalent O(1)Ba5Zr octahedra, edges with two equivalent O(2)Ba4Zr2 octahedra, faces with four equivalent O(2)Ba4Zr2 octahedra, and faces with four equivalent O(1)Ba5Zr octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(1) is bonded to five equivalent Ba(1) and one Zr(1) atom to form distorted OBa5Zr octahedra that share corners with five equivalent O(1)Ba5Zr octahedra, corners with twelve equivalent O(2)Ba4Zr2 octahedra, edges with eight equivalent O(1)Ba5Zr octahedra, and faces with four equivalent O(2)Ba4Zr2 octahedra. The corner-sharing octahedral tilt angles range from 0-57°.
Ba2ZrO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. All Ba(1)-O(2) bond lengths are 2.90 Å. There is one shorter (2.66 Å) and four longer (2.97 Å) Ba(1)-O(1) bond lengths. Zr(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedra are not tilted. Both Zr(1)-O(1) bond lengths are 2.12 Å. All Zr(1)-O(2) bond lengths are 2.10 Å. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Ba(1) and two equivalent Zr(1) atoms to form distorted OBa4Zr2 octahedra that share corners with two equivalent O(2)Ba4Zr2 octahedra, corners with twelve equivalent O(1)Ba5Zr octahedra, edges with two equivalent O(2)Ba4Zr2 octahedra, faces with four equivalent O(2)Ba4Zr2 octahedra, and faces with four equivalent O(1)Ba5Zr octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the second O site, O(1) is bonded to five equivalent Ba(1) and one Zr(1) atom to form distorted OBa5Zr octahedra that share corners with five equivalent O(1)Ba5Zr octahedra, corners with twelve equivalent O(2)Ba4Zr2 octahedra, edges with eight equivalent O(1)Ba5Zr octahedra, and faces with four equivalent O(2)Ba4Zr2 octahedra. The corner-sharing octahedral tilt angles range from 0-57°.