Redox and guest tunable spin-crossover properties in a polymeric polyoxometalate

Abstract

A bifunctionalized polyoxometalate (POM), [V6O19(C16H15N6O)2]2-, which contains a redox active hexavanadate moiety covalently linked to two tridentate 2,6-bis(pyrazol-1-yl)pyridine (1-bpp) ligands, has been prepared and characterized. Reaction of this hybrid molecule...

Activating a high-spin iron(ii) complex to thermal spin-crossover with an inert non-isomorphous molecular dopant

“…18,19 Alternatively, [Fe (bpp) 2 ] 2+ switching centres bearing functional or tether group substituents have yielded a variety of multifunctional molecules, materials and nanostructures. [20][21][22][23][24][25] However, a disadvantage of [Fe(bpp) 2 ] 2+ derivatives for SCO applications is that the high-spin complexes are prone to an angular Jahn-Teller distortion in the solid state. 26 This is an evolution of their coordination geometry along the O h -D 3h coordinate, constrained by the geometry of the tridentate bpp ligand.…”

“…18,19 Alternatively, [Fe(bpp) 2 ] 2+ switching centres bearing functional or tether group substituents have yielded a variety of multifunctional molecules, materials and nanostructures. 20–25…”

Successive redox modulation in an iron(ii) spin-crossover framework

“…Recently, redox PSM onto cyanometallate/polyoxometalate linkers has been proven to be an effective method for controlling the spin transition temperature or regulating SCO behaviors. 26–29 Especially, hysteretic three- and two-stepped SCO behaviors were achieved by oxidative addition of different halogen molecules onto the open metal sites in the cationic framework of [Fe II (TPB){Au I (CN) 2 }] + (TPB = 1,2,4,5-tetra(pyridine-4-yl)benzene). 29 However, no successive redox PSM has been investigated for SCO materials until now.…”

Making one VIV substitution for Mo on classical [MoV2O4]2+ group: the first heterobimetallic Mo–V subunit in polyoxomolybdate–bisphosphonate family

“…Polyoxometalates (POMs) are a large exceptional class of oxygen cluster compounds mainly consisting of early transition metals of group V and VI (Mo, W, V, Nb, Ta, etc.) in their high oxidation states, which have a diverse structural and compositional range as well as a great variety of catalytic, [1][2][3][4][5] electrochemical, [6][7][8] medical, 9-12 fluorescent [13][14][15] and magnetic properties [16][17][18] on the molecular level. Grafting organic moieties onto POMs by covalent bonds can unite the advantages of the inorganic metal oxide cluster and the organic components with rich functionalities to enrich the structure of POMs and enhance compatibility with other organic substrates or media.…”