An in situ, time-resolved energy dispersive powder X-ray diffraction study of the solvothermal crystallisation of the copper(II) 4,4 0 ,4 00 -benzene-1,3,5-triyl-tris(benzoate) metal-organic framework MOF-14 shows how reaction conditions must be carefully chosen to allow successful preparation of the material, since on prolonged heating at $120 C the material irreversibly collapses into Cu 2 O under solvothermal conditions in less than 2 hours. This situation is in contrast to the related Cu(II)-containing metal-organic framework HKUST-1, which shows solvothermal stability over similar temperatures and reaction times. The kinetics of crystallisation of both MOFs are examined using a mathematical model proposed by Gualtieri for zeolite crystallisation: this allows separation of the nucleation and growth regimes to yield two rate constants. Arrhenius analysis gives activation energies that reveal in both cases the crystallisations are nucleation controlled. For MOF-14 we can additionally simulate its decomposition as dissolution of the first-formed interpenetrating structure: this produces a complete picture of the solvothermal stability of MOF-14 as nucleation-growth crystallisation, with some evidence of secondary nucleation, followed by dissolution.

The structures of four iron(III) carboxylate materials with the MIL-53 structure and the guest molecules water, pyridine, or 2,6-dimethylpyridine (2,6-lutidine) have been solved and refined from high-resolution powder X-ray diffraction data. These materials have porous structures constructed from infinite chains of trans-corner-shared {FeO 4 (OH,F) 2 } octahedra cross-linked by benzenedicarboxylate ligands. With pyridine, the unit cell is partially expanded with respect to the hydrated phase, with hydrogen bonds between N donors and OH framework atoms, whereas with lutidine, water is co-sorbed to give a fully expanded version of the MIL-53(Fe) structure in which water molecules bridge the N donors of the organic molecule and the framework OH groups by hydrogen bonding. Careful dehydration of MIL-53(Fe)[2,6-lutidine,H 2 O] provides a new material, MIL-53(Fe)[2,6-lutidine 0.5 ], with an intermediate unit cell volume: in this case no host-guest hydrogen bonds are formed. Time-resolved in situ energy-dispersive X-ray diffraction shows that when exposed to an aqueous mixture of pyridine and 2,6-lutidine the hydrated MIL-53(Fe) takes up both guest molecules initially to give two distinct phases, but the ultimate product is only MIL-53(Fe)[2,6-lutidine,H 2 O].

Zn(C17H8F6O4) is the first example of a fluoro-lined nanotube organo-inorganic 3D polymeric chiral structure, which possesses two different types of isolated channels, one of them being laid out with a double spiral of CF3-groups from the ligand molecule; the structure is a new uninodal 4-connected net that only exists when bent ligands connect the centres, and the compound exhibits selective sorption and catalytic chiral recognition properties.