Mossbauer Investigations of Structural Changes in La_(0.95)Ba_(0.05)Mn_(0.98)~(57)Fe_(0.02)O_(3+δ) under Heat Treatment

摘要

The structural changes in Ba-doped lanthanum manganite, La_(0.95)Ba_(0.05)Mn_(0.98)Fe_(0.02)O_(3+δ), have been studied depending on the annealing time under different heat treatment conditions (continuous and step-by-step vacuum annealing) by Mossbauer spectroscopy and X-ray diffraction analysis. According to the X-ray data, the synthesized polycrystalline La_(0.95)Ba_(0.05)Mn_(0.98)Fe_(0.02)O_(3+δ) sample is single-phased and has a rhombohedral structure. The orthorhombic phases were obtained by annealing the synthesized sample in vacuum. It has been shown that the partial relation of orthorhombic phases varies under different vacuum heat treatment conditions and these variations have a fluctuation character.