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本文通过共沉淀工艺会成了复合氧化物Ln0.67Sr0.33MnO3(Ln=La、Pr、Nd、Sm）与传统陶瓷制各方法相比，成相温度降低约450℃．经X射线衍射分析表明，所得复合氧化物为立方钙钛矿结构，晶胞参数随稀土离子半径变化而呈规律性变化．样品的四极法电阻率测试结果表明：样品中的稀土离子Ln的离子半径对其本身的导电性起决定性的作用．应用双交换理论，只能部分地解释该实验结果．由此推测稀土离子中的4f层电子在电导过程中起一定作用．
In this paper, the composite oxide Ln0.67Sr0.33MnO3 (Ln = La, Pr, Nd, Sm) is formed by the coprecipitation process, and the phase transformation temperature is reduced by about 450 ℃ compared with the traditional ceramic method. X-ray diffraction analysis showed that the resulting composite oxide cubic cubic perovskite structure, unit cell parameters with changes in the radius of rare earth ions showed a regular change. The quadrupole resistivity of the sample shows that the ionic radius of the rare earth ion Ln in the sample plays a decisive role in its own conductivity. The application of double exchange theory can only partially explain the experimental results. It is inferred that the 4f electrons in rare earth ions play a role in the conductance.