6533b7dbfe1ef96bd1270a43

RESEARCH PRODUCT

Supramolecular Spintronic Devices: Spin Transitions and Magnetostructural Correlations in[Fe4IIL4]8+[2×2]-Grid-Type Complexes

Jean-marie LehnEsther BreuningVadim KsenofontovGavin VaughanMario RubenPhilip GütlichFranz Renz

subject

Ligand field theorySteric effectsSpintronicsStereochemistryMagnetismLigandChemistryOrganic ChemistrySpin transitionSupramolecular chemistryGeneral ChemistryCatalysisCrystallographySpin (physics)

description

The magnetism of a series of tetranuclear complexes of the [Fe4IIL4]8+ [2x2]-grid-type was investigated, revealing the occurrence of spin transition behavior within this class of compounds. The phenomenon depends directly on the nature of the substituent R(1) in the 2-position on the central pyrimidine group of the ligand L. All Fe(II) ions in compounds with R(1) substituents favoring strong ligand fields (R(1)=H; OH) remain completely in the diamagnetic low-spin state. Only complexes bearing R(1) substituents attenuating the ligand field by steric (and to a lesser extent electronic) effects (R(1)=Me; Ph) exhibit spin transition behavior triggered by temperature. In general, gradual and incomplete transitions without hysteresis were observed for magnetically active complexes. The systems described provide approaches to the development of (supra)molecular spintronics.

https://doi.org/10.1002/chem.200390259