Abstract

The La_1–xCa_xMn_0.5Co_0.5O₃ solid solutions (x = 0.2-0.6) are prepared by the Pechini method and characterized by a number of physical and chemical methods. It is shown that the oxygen nonstoichiometry in the samples significantly increases with increasing number of calcium cations in the La sublattice. The thermal analysis of the samples shows that the lattice oxygen is released at ~600 °C for all samples and that its amount increases with increasing calcium content. The in situ powder XRD data obtained in the He atmosphere indicate that the studied solid solutions with x ≥ 0.4 are unstable under these conditions and may exhibit partial structural destruction and that the ABO₃ complex oxide in the system with x = 0.6 transforms into a phase characterized by the A₂BO₄ structural type of the Ruddlesden–Popper series.