Magnetic and electrical transport properties of perovskite manganites Pr0.6Sr0.4MxMn1-xO3(M = Fe, Co, Ni).

Powder samples of ABO₃ perovskite manganites with the composition Pr_0.6Sr_0.4M_xMn_1-xO₃ (M=Fe, Co, or Ni, 0.00≤x≤0.25) were synthesized using the sol-gel method. X-ray diffraction analyses showed that all three sets of samples had a single phase with an orthorhombic structure. The magnetic moment, μ_obs, of the samples at 10 K, decreased slowly for x≤0.10, whereas μ_obs decreased rapidly for x≥0.10. The dependences of μ_obs on the doping level x for the three series of samples were fitted successfully. In the fitting process, Mn, Fe, Co, and Ni cations were assumed to be trivalent, and the magnetic moment directions of Fe³⁺, Co³⁺, and Ni³⁺ cations were assumed to be canted antiferromagnetically coupled with Mn³⁺ cations. The cant angle φ decreased with the increase in x for x≤0.10 for Fe- and Ni-doped (x≤0.15 for Co-doped) samples and increased rapidly when x≥0.10 (x≥0.15 for Co-doped) samples. These properties are discussed using an oxygen 2p itinerant electron model, which is very similar to the oxygen 2p hole model proposed by Alexandrov et al. [ABSTRACT FROM AUTHOR]