REACTION BETWEEN Nd//2O//3 AND WO//3, AND PHASE DIAGRAM OF THE SYSTEM Nd//2O//3 multiplied by (times) 2WO//3-WO//3.

In order to study the phase relation in the system Nd//2O//3-WO//3, the reaction products by solid state reaction and by confusion and annealing were examined by X-ray diffractometry and differential thermal analysis. The attainment of phase equilibria at 1000 degree C has been confirmed by the coincidence of the products from both reactions for the samples in the composition range between WO//3 and Nd//2O//3 multiplied by (times) 2WO//3. Nd//2O//3 multiplied by (times) 4. 4WO//3, Nd//2O//3 multiplied by (times) 3WO//3 and Nd//2O//3 multiplied by (times) 2WO//3 are stable intermediate compounds in this system. The composition of the compound Nd//2O//3 multiplied by (times) 4. 4WO//3 has been reconfirmed to be of this stoichiometry.