Fluoride ion donor properties in UOF 4

Abstract

Recently the adducts UOF 4·nSbF 5 (n = 1−3) were obtained from the reaction of UOF 4 with SbF 5 in SbF 5 or HF solvents and the structure of the 1:2 compound was described in terms of a fluorine-bridged network but with some contribution to the bonding from the ionic formulation [U VIOF 2][Sb VF 6] 2. Reaction of UOF 4 with the Lewis Acid pentafluorides, BiF 5, TaF 5 and NbF 5, in anhydrous HF solvent or by fusing together UOF 4/MF 5 mixtures, also yields fluorine-bridged adducts, UOF 4·2BiF 5, UOF 4·3TaF 5 and UOF 4·3NbF 5, and it has been shown that, in these complexes too, UOF 4 exhibits weak fluoride ion donor properties. The ternary adducts UOF 4·mSbF 5·nCH 3CN (m = 1,2; n = 2,6 respectively) and UF 5·xSbF5· CH 3CN (x = 1,2; y = 2,5 respectively) have been prepared by the reaction of dry acetonitrile with the appropriate binary adduct.