Study of Na substitution in La0.67Ba0.33MnO3 perovskites

The effect of Na substitution on nominal La0.67Ba0.33-x Na (x) MnO3 (0a parts per thousand currency signxa parts per thousand currency sign0.33) manganites is studied in this work. Detailed chemical and structural analyses on ceramic samples obtained at 1200 C-a similar to show that a significantly lower Na rate than the nominal one is obtained due to important Na losses during the synthesis. The losses of Na result in the appearance of impurity phases for high nominal Na rates in addition to the manganite phase with a rhombohedral structure. Structural and physical properties of the samples can be properly interpreted according to the variation of the Mn3+/Mn4+ ratio and the average ionic radius of A-site when the experimental composition of the manganite is considered.