Metal-insulator transition and spin-glass behavior in Eu2-xPbxRu2O7 system
Eu2－xPbxRu2O7中的金属-绝缘体相变和自旋玻璃态行为

The investigation on the structure, resistivity and susceptibility was carried out for Eu2-xPbxRu2O7 (x=0.0, 0.2, 0.4, 0.6, 0.8, 1.0 and 1.8) samples. It is found that the resistivity of the samples, the local magnetic moment of Ru4+ and the freezing temperature TG of spin glass decrease gradually with the increasing substitution concentration value x of Pb for Eu in Eu2-xPbxRu2O7 system. A metal-insulator (M-I) transition occurs near x=0.8. It is suggested that in this system the partial substitution of Pb2+ for Eu3+ results in the increasing of carrier concentration. And the mixing of 6p band of Pb and the t2g band of Ru 4d electrons brings about an enhancement of itinerary for Ru 4d electrons.