The Tripodal Ligand’s 4f Complexes: Use in Molecular Magnetism

Abstract

A predictable type of coordination is a key property of tripodal ligands. Homo- and heteroleptic lanthanide complexes with tripodal ligands are a representative class of compounds. However, despite the fact that many of them are paramagnetic, their magnetic behavior is poorly studied. This is because their photophysical and catalytic properties are considered more attractive. In the present review, we try to summarize the available structural information and only a few examples of data on magnetic properties in order to draw some conclusions about the prospect of such ligands in the design of quantum molecular magnets involving lanthanide (Ln) ions. We would also like to catch the reader’s attention to the fact that, despite the consideration of a large part of the currently known Ln compounds with tripodal ligands, this review is not exhaustive. However, our goal is to draw the attention of magnetochemists and theoreticians to a whole niche of air-stable Ln complexes that is still out of their field of vision.

The Synthesis, Crystal Structure, and Magnetic Properties of Mono-Scorpionate Eu(III) Complexes

“…Based on the stereochemical analysis of the coordination environment in compound 2, it was stated that the complexes [Ln(HC(Pz Me 2 ) 3 )(NO 3 ) 3 ] [42] can be used as a model system for the monoradical complexes [LnRad(NO 3 ) 3 ], since both types of compounds have the same type of coordination polyhedron (symmetry point group D 3h ) and very close Ln-donor atom distances. It is quite possible that the neutral ligand HC(Pz Me 2 ) 3 can also be used for the synthesis of bis-tripodal complexes, [Ln(HC(Pz Me 2 ) 3 ) 2 ](anion) 3 , as model systems for biradical compounds with sterically hindered paramagnetic tripods, [Ln(Rad) Me 2 ](anion) 3 , for which the corresponding ligands are under preparation [64]. As surprising as it may be, the homoleptic Ln 3+ complexes involving two balky diamagnetic tripods of type HC(Pz Me 2 ) 3 in their composition are still unknown.…”