Cs2CuF6

Cs2CuF6, also known as cesium hexafluorocuprate(IV), is an inorganic compound. It is a salt composed of cesium cations (Cs+) and hexafluorocuprate(IV) anions (CuF6^2-). This compound is notable for containing copper in the unusual +4 oxidation state, which is quite rare for copper. It is a dark-colored solid, often appearing black or very dark purple.

The synthesis of Cs2CuF6 typically involves strong oxidizing agents and fluorine sources at elevated temperatures. One common method is the reaction of copper(II) fluoride with cesium fluoride in the presence of elemental fluorine or a powerful fluorinating agent like XeF2. The high oxidation state of copper in this compound makes it a potent oxidizing agent itself.

Cs2CuF6 is highly reactive and sensitive to moisture and heat. When exposed to water, it tends to decompose, releasing oxygen and forming copper(II) compounds. Its instability limits its practical applications, and it is primarily of interest in research settings for studying the chemistry of high oxidation state transition metal compounds and fluorine chemistry. Due to its reactivity and the presence of fluorine, appropriate safety precautions, including handling in inert atmospheres and with protective equipment, are necessary.