Room temperature syntheses of lanthanoid tetrafluorides (LnF4, Ln = Ce, Pr, Tb)

CeF3 is oxidised to CeF4 at room temperature by elemental fluorine in liquid anhydrous hydrogen fluoride (aHF) as a solvent. The reactions of ultraviolet photolysed F2 with Pr6O11 or Tb4O7 in aHF at room temperature produce PrF4 or TbF4, respectively, in quantitative yield. The synthesis described of PrF4 represents a convenient approach requiring only commercially available reactants.