Re-Determination of the Crystal Structure of MIL-91(Al).

The structure of one of the first permanently porous metal phosphonates, MIL-91(Al) was re-determined using high resolution synchrotron powder X-ray diffraction data. The new model is in a lower symmetry space group, with no disordered ligands in the structure, whilst remaining otherwise consistent with the reported compound. New milder synthetic conditions were also developed.