Al-2[O3PC2H4PO3](H2O)(2)F-2 center dot H2O: a novel aluminium diphosphonate

The synthesis and crystal structure of the novel aluminium diphosphonate Al-2[O3PC2H4PO3](H2O)(2)F-2. -H2O is described; the material consists of chains of AlO4F2 octahedra linked together by ethylene-diphosphonate units to form a structure with channels running parallel to the a axis which contain extra-framework water molecules that can be desorbed.