Crystalline‐State Reaction with Allosteric Effect in Spin‐Crossover, Interpenetrated Networks with Magnetic and Optical Bistability

A net change: A fully reversible ligand substitution involving coordination/uncoordination of gaseous water and pyrimidine induces the repetitive allosteric transformation of three interpenetrated nets into a single three-dimensional net. The transformation does not affect the crystallinity of the sample but alters significantly the spin-crossover transition; the compound shows magnetic and chromatic bistability (see picture).