A Dynamic Measurement Study of Resistance in Synthesis Process of CeTbO3 under High Pressure and High Temperature

The resistance of oxides CeTbO3, CeO2, Tb4O7 and mixture CeO2+Tb4O7 (Ce∶Tb=1∶1) has been measured from room temperature to 800 ℃ at 4.0 GPa and 0.5 GPa. All of them show semiconducting character of resistance. The up-and-down changes of the mixture and Tb4O7 have been found at 0.5 GPa above 600 ℃. X-ray diffraction shows that corresponding to this change, there is a change on the structure which might closely relate to the valence fluctuation from Tb4+ to Tb3+.