Rational design of covalently bridged [FeIII2MIIO] clusters

Abstract

We are reporting the first supramolecular dimeric units of basic carboxylates. The neutral [Fe^III₂M^IIO] motif for different 3d M metals is covalently bound through 2,2′-bipyrimidine. We have structurally characterized the hexanuclear clusters and the related trinuclear building blocks. Their magnetic properties have been fully analyzed and DFT calculations have been performed as a supplementary tool. All results evidence a weak antiferromagnetic interaction through the bpym bridge between isolated spin ground states (in some examples) arising from intra-Fe₂MO core exchange couplings.