Copper(II) fluoride

Copper(II) fluoride is slightly soluble in water, but starts to decompose in hot water, producing basic F− and Cu(OH)+ ions. ==Structure==

Copper(II) fluoride has a monoclinic crystal structure and cannot achieve a higher-symmetry structure. It forms rectangular prisms with a parallelogram base. Each copper ion has four neighbouring fluoride ions at 1.93 Å separation and two further away at 2.27 Å. and leads to a distorted rutile structure similar to that of chromium(II) fluoride, , which is a d4 compound. ==Synthesis==

Copper(II) fluoride can be synthesized from copper and fluorine at elevated temperatures. At a 53% conversion is achieved. :Cu + F2 → CuF2 ==Uses==

Cupric fluoride catalyzes the decomposition of nitric oxides in emission control systems. Copper(II) fluoride can be used to make fluorinated aromatic hydrocarbons by reacting with aromatic hydrocarbons in an oxygen-containing atmosphere at temperatures above 450 °C (842 °F). This reaction is simpler than the Sandmeyer reaction, but is only effective in making compounds that can survive at the temperature used. A coupled reaction using oxygen and 2 HF regenerates the copper(II) fluoride, producing water. This method has been proposed as a "greener" method of producing fluoroaromatics since it avoids producing toxic waste products such as ammonium fluoride. : ==Reactions==

It loses fluorine in the molten stage at temperatures above 950 °C (1742 °F). :2 CuF2 → 2 CuF + F2 :2 CuF → CuF2 + Cu The complex anions CuF3−, CuF42− and CuF64− are formed if CuF2 is exposed to substances containing fluoride ions F−. ==References==