Аннотация:Reactions between XeF2 or alkali metal tetrafluorohalogenates(III) and Rare Earth ele-ments oxides, ZrO2, and HfO2 have been studied. The formation conditions of the Binary and complex fluorides have been investigated. The comparison of the fluorination activity of Xe(II), Cl(III) , and Br(III) fluorides has been proposed.