Rietveld Refinement of Crystal Phases (Ca1-xLax)MnO3 with Perovskite-Type Structure
Two nanopowders with nominal compositions (Ca0.7La0.3)MnO3 (CLM) and (Ca0.7La0.3)(Mn0.8Ce0.2)O3 (CLMC) were synthesized by a modified glycine/nitrate procedure. XRD analysis revealed binary phase mixture in both samples. The influence of La and Ce on unit cell parameters, atom positions, and average bond distances were analyzed. According to these results and refined occupation factors of La and Ca, as well as quantitative phase analysis it was found that the CLM sample consists of 85 mass.% of Ca0.62La0.38MnO3 and 15 mass.% of Ca0.99La0.01MnO3, while the CLMC sample consists of 70 mass.% of Ca0.58La0.42MnO3 and 30 mass.% of CeO2. Microstructure size-strain analysis was performed and the Rietveld refinement gave crystallites of about 100 Å. TEM images showed particle sizes of about 100-500 Å.
Dragan P. Uskoković, Slobodan K. Milonjić and Dejan I. Raković
J. Dukić et al., "Rietveld Refinement of Crystal Phases (Ca1-xLax)MnO3 with Perovskite-Type Structure", Materials Science Forum, Vol. 555, pp. 231-236, 2007