EFFECT OF HIGH PRESSURES ON THE ELECTRICAL PROPERTIES OF THE OXIDE CE0.8CU3V4O12

The electrical properties of the oxide Ce0.8Cu3V4O12 were studied at pressures up to 50 GPa. The samples have been synthesized by barothermal method. These compounds crystallize in the cubic symmetry with a perovskite-type structure. At ambient pressure in the temperature range from 10 to 300 K Ce0.8Cu3V4O12 - oxide has a metallic conductivity. Electrical resistance of the examined compounds measured at room temperature decreases when the pressure is raised from 16 to 50 GPa. There are two interval, where the resistance first falls rapidly with the pressure increase, and then the rate of the drop in resistance slows sharply. The baric dependencies of the magnetoresistance were obtained at the magnetic field up to 1 T. The values of the magnetoresistance are negative and amount 2% at pressure 22 GPa. The pressure range PT was determined, where a significant change of properties takes place. The results obtained for Ce0.8Cu3V4O12-oxide and the data of compounds ACu3V4O12 (A - Gd, Tb, Er, Tm) have been compared. A shift of the PT regions towards higher pressures with increasing serial number A was found. The manifestation of the effect of chemical contraction may be associated with a change in the crystal and electronic structure is assumed.