LOW-TEMPERATURE SPECIFIC-HEAT MEASUREMENTS ON THE NDCOXFE1-XO3 SYSTEM

Low-temperature specific heat measurements have been carried out on the NdCoxFe1-xO3 perovskite system (x = 0, 0.25, 0.5, 0.9, 1). Magnetic ordering of Nd3+ ions have been observed in NdCoO3 (at 1.20 K) and NdFeO3 (at 1.05 K). The studied dilutions, unlike the pure Fe or Co compounds, do not show a magnetic order of the Nd ions due to the stronger molecular field caused by decompensation of the internal field upon the introduction of the (Co3+) magnetic Vacancies in the antiferromagnetically ordered Fe subsystem. The specific heat curve of the system at x = 0.9 resembles spin-glass behaviour.