Thermo- and electro-switchable Cs⊂{Fe4–Fe4} cubic cage: spin-transition and electrochromism

A mixed valence Cs⊂{Fe4-Fe4} cyanido-cube was synthesized and structurally characterized. The molecule, which is robust in solution, shows remarkable electronic versatility. Electrochromic properties associated with nine different electronic states are observed in solution together with a thermo-induced spin-transition in the solid state.