Nine new vanadium oxyfluorides, containing ten different oligomeric vanadium (oxy)fluoride anions have been prepared by solvothermal synthesis in water-ethylene glycol and using organic cations as co-crystallising agents. Crystal structures are reported for each. Amongst the ten structure types, five represent previously unobserved moieties, including one monomeric unit (cis-[VOF4(H2O)]2-), two dimers ([V2O2F6(H2O)2]2- and [V2O2F8]4-) and two tetramers (both isomers of composition [V4O4F14]6-). Structural relationships between the various units are discussed, together with some rationalisation of their occurrence as a function of synthetic variables.

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The solvothermal synthesis of a new series of organically templated vanadium oxyfluorides is presented. The materials were synthesised from identical starting mixtures using temperature as the only independent variable. This shows a trend towards increasing dimensionality and decreasing vanadium oxidation state as a function of temperature. The materials were synthesised from a system containing V 2 O 5 -HF-H 2 O-ethylene glycol-piperazine which resulted in four new structure types, together with a previously known phase. 1) consists of V (V) -centred monomeric units and V (IV) edge-sharing dimers, which are held together by hydrogen bonding to form infinite chains. 2) features a Y-shaped tetramer containing both V (III) and V (IV) -centred octahedra which are held together via hydrogen bonding from the water molecules to form infinite sheets. 3) is a complex chain containing five different V-centred octahedra, which shares structural similarities with compound (2). The inter-relations between these three structure types as a function of temperature, together with two further compounds isolated from this system, are discussed.

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An exploratory study of the hydrothermal chemistry of vanadium in HF solutions has resulted in the preparation of four new vanadium (III) fluorides with chainlike structural motifs. [NH4]2[VF5] (1) and [C2N2H10][VF5] (2) feature infinite chains of trans corner-sharing VF4F2/2 octahedra, [C4N2H6][VF5].H2O (3) has cis corner-sharing [VF4F2/2]infinity chains, and [C10N2H8][VF3] (4) has trans corner-sharing [VF2F2/2]infinity chains bridged into sheets by the 4,4'-bipy linker. All four compounds exhibit antiferromagnetic behavior.