Berkelium(III) fluorideBerkelium fluoride is a binary inorganic compound of berkelium and fluorine with the chemical formula.SynthesisThe compound can be prepared by treating with a gaseous mixture of and HF at 600 °C.Physical propertiesBerkelium trifluoride forms a yellow-green solid with two structures. At low temperature, it is orthorhombic, with lattice parameters a = 670 pm, b = 709 pm, and c = 441 pm. At high temperature, it is trigonal, with lattice parameters a = 697 pm and c = 714 pm. The transition temperature of is between 350 and 600 °C.Chemical propertiesBerkelium trifluoride is reduced by lithium to obtain metallic berkelium: