Influence of grain distribution on the structural magnetic behavior of La0.67Sr0.33MnO3 nano-manganites.

Nano-size polycrystalline La0.67Sr0.33MnO3 was synthesized via co-precipitation (LSMO-CP) and sol-gel (LSMO-SG) method. X-ray diffraction (XRD) technique revealed that all the samples were trigonal crystal structure with space group of R-3c. Rietveld refinement analysis showed that elongation of c-axis and smaller a-b plane was observed in SG sample as compared with CP sample. Micrograph shows that all samples having grain size smaller than 1 μm. Higher coercivity and lower saturation magnetization were observed for SG sample which has smaller (∼100 nm) and narrower particle size distribution as compared to CP sample. This variation was believed to be due to the dead layer and domain effect. All prepared nano-size manganites are non-single domain particles and non-superparamagnetic (ferromagnetic) behavior. [ABSTRACT FROM AUTHOR]