Actinium(III) fluoride (AcF3) is an inorganic compound, a salt of actinium and fluorine.
Synthesis Actinium fluoride can be prepared in solution or by a solid-state reaction. In the first method, actinium hydroxide is treated with hydrofluoric acid and the product precipitates:
In the solid-state reaction, actinium metal is treated with hydrogen fluoride gas at 700 °C in a platinum crucible.Meyer, Gerd and Morss, Lester R. (1991) Synthesis of lanthanide and actinide compounds. Springer. . pp. 87–88
Properties Actinium fluoride is a white solid that reacts with ammonia at 900–1000 °C to yield an actinium oxyfluoride: AcF3 + 2NH3 + H2O -> AcOF + 2NH4F
While lanthanum oxyfluoride is easily formed by heating lanthanum fluoride in air, a similar treatment merely melts actinium fluoride and does not yield AcOF.
References