Graphite fluorouranates and oxofluorouranates

First and second stage graphite fluorouranates were prepared by the reactions of graphite with UF6 or beta-UF5. A second stage compound was formed when UO2F2 was reacted with graphite in the presence of elemental fluorine. UF6 reacts directly with graphite at ambient temperature. However, involatile fluorides react with graphite only in the presence of solvents at ambient temperature. The degree of intercalation of these fluorides and oxofluoride is explained by the enthalpy of formation of the fluorouranate and oxofluorouranate anions from the uranium fluorides and oxofluoride respectively, as has been reported previously for other intercalation reactions of binary fluorides.