XeF6

Xenon hexafluoride (XeF6) is a chemical compound composed of xenon and fluorine, belonging to the family of xenon fluorides. It is a highly reactive, hypervalent molecule in which xenon is formally assigned a high oxidation state. The compound is notable for its fluxional structure, with rapid rearrangement of fluoride ligands around the xenon center.

Preparation and properties. XeF6 is typically prepared by fluorinating xenon fluoride precursors, such as XeF4, under strongly fluorinating conditions and careful control of temperature and moisture. The compound is extremely reactive toward water and many organic substrates. It hydrolyzes in moisture to form xenon oxide species and hydrofluoric acid, and it decomposes upon heating. Because of its sensitivity, XeF6 is handled under strictly dry, inert conditions in specialized laboratories.

Structure and bonding. In the gas phase, XeF6 exhibits fluxional behavior, with rapid exchange of fluoride ligands that prevents a single, static geometry from being observed easily. In the solid state, the structure is disordered, and studies indicate a dynamically rearranging coordination environment around xenon. The bonding is described within the framework of hypervalent bonding, consistent with other heavy xenon fluorides, and involves extended Xe–F interactions that accommodate six ligands around xenon.

Reactions and uses. XeF6 is a powerful fluorinating and oxidizing agent used primarily in inorganic synthesis to introduce fluorine or to generate related xenon fluoride species. It forms adducts with Lewis bases and participates in fluoride-transfer reactions, but its extreme reactivity and moisture sensitivity limit practical applications.

Safety. XeF6 is corrosive and reacts vigorously with water and with many organic materials, releasing toxic and corrosive gases and liquids such as HF. Handling requires dry, inert atmosphere conditions, appropriate shielding, and protective equipment.