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 + CuF2
As a result of this disproportiontion, samples slowly become light cyan in colour, the colour of copper(II) fluoride.
^Gulliver, D. J.; Levason, W.; Webster, M. (1981). "Coordination Stabilised Copper(I) Fluoride. Crystal and Molecular Structure of Fluorotris(triphenylphosphine)copper(I)·Ethanol (1/2), Cu(PPh3)3F·2EtOH". Inorg. Chim. Acta52: 153–159. doi:10.1016/S0020-1693(00)88590-4.
^Francis, Simon G.; Matthews, Steven L.; Poleshchuk, Oleg Kh.; Walker, Nicholas R.; Legon, Anthony C. (2006-09-25). "N2-Cu-F: A Complex of Dinitrogen and Cuprous Fluoride Characterized by Rotational Spectroscopy". Angewandte Chemie118 (38): 6489–6491. doi:10.1002/ange.200601988.Cite uses deprecated parameters (help)