Guest-tuned spin crossover in flexible supramolecular assemblies templated by a halide (Cl-, Br- or I-)

Abstract

Ligand 1,3-bis(3-(pyridin-2-yl)-1H-pyrazol-5-yl) benzene, L, forms mononuclear spin crossover complexes [FeL3](2+) with pendant arms that cause them to dimerize through numerous intermolecular interactions forming supramolecular (X@[FeL3](3+) cations. They have the flexibility to encapsulate Cl-, Br- or I-), which allow tuning the magnetic properties, in the solid state and in solution.