Studies on oxoperoxofluorovanadates (V)

Abstract

Two oxoperoxofluoro complexes of vanadium, viz., (NH 4) 2 [VO(O 2) (OH)F 2] and K 4 [V 2O 3(O 2) 2F 4] have been prepared by crystallising solutions of vanadium pentoxide in aqueous hydrofluoric acid with ammonium or potassium fluoride solutions containing hydrogen peroxide at 5°C. The orange crystalline substances are quite stable. They are very weakly paramagnetic and display strong ν(VO) and ν(OO) bands in their i.r. spectra. The TGA curves of the complexes show horizontals corresponding to the formation of (NH 4) 4 [V 2O 5F 4] and K 4[V 2O 5F 4] respectively which have actually been isolated. These appear to be oxobridged complexes. The x-ray patterns of the two peroxo complexes are distinctly different.