Thermo-, piezo-, photo- and chemo-switchable spin crossover iron(II)-metallocyanate based coordination polymers

The design of coordination polymers (CPs) with switch and memory functions is an important subject of current interest in the search for new advanced materials with potential applications. Implementation of CPs with electronically labile iron(II) building blocks able to undergo cooperative spin crossover (SCO) behavior is a singular approach to this end. This review provides an up to date survey of a new generation of iron(II)-metallocyanate based spin crossover coordination polymers (SCO-CPs) developed during the last decade. These new solids feature structural diversity, supramolecular isomerism, interpenetrating frameworks, structure flexibility, reversible solid-state chemical reactions, metallophilic interactions, porosity, physi- and chemisorption, or processability at nanoscale level, in addition to inherent SCO properties.