Density 7.1 g/cm³ | ||
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Copper(I) fluoride is an inorganic compound with the chemical formula CuF. Its existence is uncertain. It was reported in 1933 to have a sphalerite-type crystal structure. Modern textbooks state that CuF is not known, since fluorine is so electronegative that it will always oxidise copper to its +2 oxidation state. Complexes of CuF such as [(Ph3P)3CuF] are, however, known and well characterised.
Synthesis and reactivity
It can be formed by the reduction of copper(II) fluoride. Unlike copper(I) chloride, copper(I) fluoride tends to disproportionate into copper(II) fluoride and copper in a one-to-one ratio at ambient conditions, unless it is stabilised through complexation as in the example of [Cu(N2)F].
2CuF → Cu + CuF2As a result of this disproportiontion, samples slowly become light cyan, the colour of copper(II) fluoride.