A complete review of all known octacyanide-based clusters with an extensive discussion of their structures, magnetic properties and multifunctionality.

Functional materials incorporating cyanido-bridged Dy^IIICo^III molecules combine visible photoluminescence and slow magnetic relaxation, both switchable by the level of humidity within the reversible room temperature dehydration process.

An alternating bimetallic {(H₃O)[Ni^III(cyclam)][Fe^II(CN)₆]·5H₂O}_n chain undergoes reversible dehydration at 40 °C accompanied by electron transfer which leads to Ni^II–Fe^III in about 50% of metal centres. The hydrated dark blue form is a paramagnet while the dehydrated yellowish-green form shows ferromagnetic coupling between neighbouring Ni^II and Fe^III.

Unique hybrid organic–inorganic coordination networks, three-dimensional [(UO₂)₂(OH)(4,4′-bpdo)₂][M(CN)₆]·nH₂O (M = Co, 1; Rh, 2; Ir, 3) and layered [(UO₂)₂(OH)₂(4,4′-bpdo)₂][Pt(CN)₆]·H₂O (4), employing cyanide, hydroxide and 4,4′-bpdo bridges, are reported. They exhibit vibronically coupled charge transfer emission of uranyl ions, whose colour is tunable from green to orange by the implemented hexacyanidometallates.