Phonon Raman scattering in LaMn₁₋xCoxO₃ (x = 0, 0.2, 0.3, 0.4, and 1.0)

Abstract

The Raman-active phonons in perovskite-like LaMn₁–xCoxO₃ (x = 0, 0.2, 0.3, 0.4, and 1.0) were studied by measuring Raman spectra at temperatures of 295 and 5 K. The changes in the spectra with Co doping are correlated with the decrease of orthorhombic distortions. Surprisingly more phonon lines than allowed for the rhombohedral LaCoO₃ structure were observed.