Application of spin-crossover water soluble nanoparticles for use as MRI contrast agents.

Water soluble spin-crossover (SCO) iron(II) nanoparticles (NPs) were synthesized by the polyethylene glycol (PEG) coating of [Fe(Htrz)(NHtrz)](BF) (x = 0, 0.1, 0.5 and 1).

Intermolecular Interaction Tuning of Spin-Crossover Iron(III) Complexes with Aromatic Counteranions.

Iron(III) spin-crossover (SCO) complexes [Fe(qsal)]BS·MeOH·HO (1), [Fe(qsal)](NS)·MeOH (2), [Fe(qnal)](NS) (3), and [Fe(qnal)]PS·MeOH·CHCl (4) (Hqsal, N-(8-quinolinyl)salicylaldimine; Hqnal, N-(8-quinolinyl)-2-hydroxy-1-naphthaldimine; BS, benzenesulfonate; NS, 1-naphthalenesulfonate; PS, 1-pyrenesulfonate) have been synthesized and characterized by X-ray structure determinations and temperature-dependent magnetic susceptibility measurements. The aromatic counteranions BS, NS, and PS can be used for the tuning of intermolecular coupling through a variety of weak interactions. All of the complexes show temperature-dependent SCO behavior.

Direct monitoring of spin transitions in a dinuclear triple-stranded helicate iron(ii) complex through X-ray photoelectron spectroscopy.

A dinuclear helical iron(ii) complex of a new ditopic thiazolylimine ligand (L) has been synthesised via supramolecular assembly. The resulting dinuclear helical cylinder [FeL]·4BF was investigated by variable temperature X-ray crystallography, ESI high resolution mass spectrometry, CHN analysis, FT-IR and UV-Vis spectroscopy. The nature of the spin transition was investigated by magnetic susceptibility measurements, and confirmed by VT-SCXRD and X-ray photoelectron spectroscopy.