Cs2Ba2O3 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. Ba(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form a mixture of distorted edge and corner-sharing BaO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cs(1) and four equivalent Ba(1) atoms to form corner-sharing OCs2Ba4 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cs(1) and two equivalent Ba(1) atoms.
Cs2Ba2O3 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. The Cs(1)-O(1) bond length is 3.31 Å. There is one shorter (2.85 Å) and one longer (2.92 Å) Cs(1)-O(2) bond length. Ba(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form a mixture of distorted edge and corner-sharing BaO4 tetrahedra. There is one shorter (2.70 Å) and one longer (2.73 Å) Ba(1)-O(1) bond length. Both Ba(1)-O(2) bond lengths are 2.53 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cs(1) and four equivalent Ba(1) atoms to form corner-sharing OCs2Ba4 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cs(1) and two equivalent Ba(1) atoms.