Vaporization of Rare-Earth Oxides

A study of the vaporization of La₂O₃, Nd₂O₃, and Y₂O₃ at high temperatures has been carried out by the Knudsen effusion technique. The methods employed, the results of the measurements, and the low-temperature heat capacities of these materials, which were determined for the purpose of calculating thermal functions of the oxides, are discussed. All the foregoing oxides react with tantalum, forming gaseous tantalummonoxide as a principal product. Cubic tantalates of lanthanum and neodymium are also formed in these reactions.