Cs2Sr2O3 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Sr(1) is bonded to one O(1) and three equivalent O(2) atoms to form a mixture of edge and corner-sharing SrO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Cs(1) and two equivalent Sr(1) atoms to form corner-sharing OCs4Sr2 octahedra. The corner-sharing octahedral tilt angles are 61°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cs(1) and three equivalent Sr(1) atoms.
Cs2Sr2O3 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. There is one shorter (3.04 Å) and one longer (3.11 Å) Cs(1)-O(1) bond length. There is one shorter (3.06 Å) and one longer (3.42 Å) Cs(1)-O(2) bond length. Sr(1) is bonded to one O(1) and three equivalent O(2) atoms to form a mixture of edge and corner-sharing SrO4 tetrahedra. The Sr(1)-O(1) bond length is 2.41 Å. There are a spread of Sr(1)-O(2) bond distances ranging from 2.45-2.48 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Cs(1) and two equivalent Sr(1) atoms to form corner-sharing OCs4Sr2 octahedra. The corner-sharing octahedral tilt angles are 61°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cs(1) and three equivalent Sr(1) atoms.