57Fe Mössbauer Spectroscopy as a Tool for Study of Spin States and Magnetic Interactions in Inorganic Chemistry.

Ernő Kuzmann,Roland Szalay,Zoltán Klencsár,Zoltán Homonnay

doi:10.3390/molecules26041062

Ernő Kuzmann, Roland Szalay + Show 2 more

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https://doi.org/10.3390/molecules26041062

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Abstract

In this mini-review of our research group’s activity, the application of 57Fe Mössbauer spectroscopy in studies of electronic structure, coordination environment, and magnetic interactions in an interesting series of Fe(II/III) compounds selected is discussed. We selected two prominent phenomena that arose during investigations of selected groups of compounds carried out at different periods of time: (1) very high magnetic hyperfine fields observed at low temperatures; (2) changes in the oxidation state of the central iron atom of complexes in the solid state during interactions with gaseous O2/H2O mixtures, resulting in spin crossover (SCO).

Highlights

One very interesting field of modern molecular chemistry is the preparation and investigation of properties of specially designed single molecules, metal clusters, or groups of molecules that exhibit cooperative effects and extended magnetic interactions [1,2,3]
Single-molecule magnets (SMMs) known to date [3,6,7,8,9] usually contain clusters of paramagnetic ions bound to simple ligands, surrounded by organic molecular ligands
In this mini-review, we present some of our research group’s recent results on spin transitions and magnetic coupling in oxygenated iron(II)/(III) phthalocyanines and twocoordinate linear iron(II) complexes, which were studied with extensive use of Mössbauer spectroscopy

Summary

Introduction

One very interesting field of modern molecular chemistry is the preparation and investigation of properties of specially designed single molecules, metal clusters, or groups of molecules that exhibit cooperative effects and extended magnetic interactions [1,2,3]. For iron-containing inorganic compounds, solid state phases, materials, or alloys, 57Fe Mössbauer spectroscopy has a great advantage over other methods because it allows researchers to obtain information about (1) the metal oxidation state; (2) the spin state; (3) the iron center microenvironment; and (4) the absence/presence and origin of hyperfine magnetic fields. Mössbauer spectroscopy is suitable for detecting and distinguishing magnetic coupling (ferromagnetic, antiferromagnetic, and ferrimagnetic) between metal centers This task can be achieved by examining the exchange interactions. Cules 2020, 25, x FOR PEER REVIEW MolecuMlesol2ec0u2l0es, 22052, 1x, F26O, R10P62EER REVIEW

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