Аннотация:The substituted orthoferrite La0.67Sr0.33FeO3-γ was studied using scanning electron microscopy, X-ray diffraction (XRD), and Mossbauer and Raman spectroscopy. A series of vacuum annealing in the temperature range of 200–650◦C was performed, resulting in negligible changes in the crystal structure of samples. The volume of the pseudocubic unit cell increased continuously with raising temperature up to 450◦C. It follows from the Mossbauer measurements that at room temperature Fe ions were characterized by an averaged-valence state. The vacuum annealing induced oxygen vacancies and changed the averaged-valence state of Fe ions. Sufficiently good correlations among the Mossbauer, XRD, and Raman spectroscopy data were obtained.
