EPR as a Tool for Study of Isolated and Coupled Paramagnetic Centers in Coordination Compounds and Macromolecules of Biological Interest

Abstract

Abstract Continuous Wave Electron Paramagnetic Resonance (CW EPR) is an essential spectroscopic tool for study of systems containing unpaired electrons. The potential capability of the technique has extended its use beyond being solely by experts, and today it is widely used by non‐specialists. In this microreview we present selected examples together with basic theoretical aspects necessary for understanding of the EPR properties of isolated paramagnetic centers and assemblies of them that may be coupled by very weak isotropic exchange interactions (<0.1 cm –1 ) when linked by diamagnetic extended chemical pathways. The goal of the paper is to show in a unified way the information that CW EPR can provide for understanding of the electronic structures and magnetic properties of distinct types of paramagnetic transition‐metal‐ion‐containing systems of biological relevance, such as low‐molecular‐weight inorganic complexes and metalloproteins.