Caesium propano-ate monohydrate.

Caesium propano-ate monohydrate, Cs·CHO ·HO, is composed of two symmetry-independent Cs cations, which are situated on the special position 4 of space group 2 , one symmetry-independent propano-ate mol-ecule in a general position and a pair of water mol-ecules also situated on special position 4. Two pairs of these symmetry-independent cations, four propano-ate mol-ecules and two pairs of symmetry-independent water mol-ecules form a repeat unit. These units form columns that are directed along the axis and possess symmetry 2. There are four such columns passing through each unit cell. Each column is inter-connected to its neighbours by four bifurcated three-centred O-H⋯O (w = water, p = propano-ate) hydrogen bonds of moderate strength. There are also four intra-molecular O-H⋯O hydrogen bonds of moderate strength within each column. One Cs cation is coordinated by six oxygen atoms (two water and four carboxyl-ate) in a trigonal-prismatic geometry, while the other Cs cation is coordinated by four water and four carboxyl-ate O atoms in a tetra-gonal-prismatic arrangement.