Design and Assembly of Covalently Functionalised Polyoxofluorovanadate Molecular Hybrids. Issue 15 (14th February 2018)

• Record Type: Journal Article
• Authors: Nicolaou, Maria; Papanikolaou, Michael G.; Tsipis, Athanassios C.; Kabanos, Themistoklis A.; Keramidas, Anastasios D.; Sproules, Stephen; Miras, Haralampos N.
• Is Part Of: Chemistry. Volume 24:Issue 15(2018)
• Page Start: 3836
• Page End: 3845
• Publication Date: 2018-02-14
• Subjects: electron paramagnetic resonance -- mass-spectroscopy -- polyoxometalates -- self-assembly -- vanadium; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201705730
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Mixed‐valent polyoxometalate (POM) clusters are one of the most interesting host species, showing a wide range of structural features and properties. The facile preparation and functionalisation of a mixed‐valent polyoxofluorovanadates is reported, where two electrons are trapped to antipodal sites of the clusters. The first members of this family of clusters with the general formula, [V V 12 V IV 2 O16 ( μ ‐O)10 ( μ 3 ‐O)10 ( μ 3 ‐F)2 (L)2 ] 6−, where L: py=pyridine (1 ); pyr=pyrazine (2 ); im=imidazole (3 ), are unique organic‐inorganic hybrids with the addition of a N ‐donor ligand at either end of the polyoxofluorovanadate. The composition and connectivity of1 –3 were characterised by single‐crystal X‐ray diffraction and electrospray ionisation mass spectrometry. Electron paramagnetic resonance spectroscopy revealed that the two well‐separated V IV ions in each cluster are fully uncoupled with J= 0, giving a degenerate singlet–triplet ground state. This attenuation of the exchange interaction is probed with density functional theoretical calculations that reveal that the inclusion of the fluoride ion in the cluster produces a bond pathway biased toward destructive interference between competing ferromagnetic and antiferromagnetic interactions. These robust molecular materials are the ideal combination of desirable electronic properties, with an organic handle with which they can be integrated into spintronic circuitry for molecular devices. Abstract : V for victory : The facile preparation and functionalisation of a mixed‐valent polyoxofluorovanadates is reported, where two electrons are trapped to antipodal sites of the clusters. The first members of this family of clusters are unique organic‐inorganic hybrids with the addition of a N ‐donor ligand at either end of the polyoxofluorovanadate.