Beschreibung:
<jats:p>The title compound, {[Ba<jats:sub>7</jats:sub>(C<jats:sub>3</jats:sub>H<jats:sub>5</jats:sub>O<jats:sub>2</jats:sub>)<jats:sub>14</jats:sub>]·0.946C<jats:sub>3</jats:sub>H<jats:sub>6</jats:sub>O<jats:sub>2</jats:sub>·4H<jats:sub>2</jats:sub>O}<jats:sub><jats:italic>n</jats:italic></jats:sub>, is represented by a metal–organic framework structure that is held together by Ba—O—Ba bonds, as well as by O—H...O hydrogen bonds of moderate strength. The structure comprises of four independent Ba<jats:sup>2+</jats:sup>cations (one of which is situated on a twofold rotation axis), seven independent propionate and two independent water molecules. The bond-valence sums of all the cations indicate a slight overbonding. There is also an occupationally, as well as a positionally disordered propionic acid molecule present in the structure. Its occupation is slightly lower than the full occupation while the disordered molecules occupy two positions related by a rotation about a twofold rotation axis. In addition, the methyl group in the symmetry-independent propionic acid molecule is also disordered, and occupies two positions. Each propionic acid molecule coordinates to just one cation from a pair of symmetry-equivalent Ba<jats:sup>2+</jats:sup>sites and is simultaneously bonded by an O—H...O<jats:sub>propionate</jats:sub>hydrogen bond. This means that on a microscopic scale, the coordination number of the corresponding Ba<jats:sup>2+</jats:sup>site is either 9 or 10. The methyl as well as hydroxy hydrogen atoms of the disordered propionic acid molecule were not determined.</jats:p>