Caesium hexafluorocobaltate(IV)
Caesium hexafluorocobaltate(IV) is an inorganic chemical compound with the formula Cs2[CoF6]. It is a dark brown or black solid, existing as a complex salt composed of caesium cations (Cs+) and the hexafluorocobaltate(IV) anion ([CoF6]2-). The compound is notable for containing cobalt in the relatively uncommon +4 oxidation state.
The hexafluorocobaltate(IV) anion features a cobalt(IV) ion coordinated by six fluoride ligands in an octahedral geometry. The compound is a strong oxidizing agent due to the high oxidation state of cobalt.
Caesium hexafluorocobaltate(IV) is typically synthesized by reacting caesium chloride (CsCl) with cobalt(II) chloride (CoCl2) in the presence of fluorine gas (F2) at elevated temperatures. The fluorine gas acts as the oxidizing agent, converting cobalt(II) to cobalt(IV).
The compound reacts readily with water, resulting in the evolution of oxygen and the formation of cobalt(II) species. Due to its strong oxidizing nature and reactivity, it requires careful handling and storage under anhydrous conditions to prevent decomposition. It finds uses in research contexts as a fluorinating agent and in the study of high oxidation state transition metal complexes.