Ba3Ti3O8 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to two equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form TiO5 square pyramids that share corners with three equivalent Ti(2)O6 octahedra and corners with two equivalent Ti(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 1-8°. In the second Ti site, Ti(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form corner-sharing TiO6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Ti(1), and one Ti(2) atom. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ti(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Ti(1), and one Ti(2) atom.
Ba3Ti3O8 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to two equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms. Both Ba(1)-O(2) bond lengths are 2.89 Å. There is one shorter (2.83 Å) and two longer (2.85 Å) Ba(1)-O(3) bond lengths. There are a spread of Ba(1)-O(1) bond distances ranging from 2.86-2.94 Å. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Both Ba(2)-O(3) bond lengths are 2.88 Å. All Ba(2)-O(1) bond lengths are 2.86 Å. All Ba(2)-O(2) bond lengths are 2.90 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form TiO5 square pyramids that share corners with three equivalent Ti(2)O6 octahedra and corners with two equivalent Ti(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 1-8°. The Ti(1)-O(3) bond length is 1.90 Å. Both Ti(1)-O(1) bond lengths are 1.99 Å. Both Ti(1)-O(2) bond lengths are 2.03 Å. In the second Ti site, Ti(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form corner-sharing TiO6 octahedra. Both Ti(2)-O(3) bond lengths are 2.06 Å. All Ti(2)-O(1) bond lengths are 2.05 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Ti(1), and one Ti(2) atom. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ti(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ti2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded in a distorted linear geometry to one Ba(2), three equivalent Ba(1), one Ti(1), and one Ti(2) atom.