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用固态反应法制备了具有单相结构的La0.5Ca0.5-xBaxMnO3系列样品，其结构随Ba含量增加由立方晶系转变为典型的正交晶系．零场下输运性质实验表明，在较低掺杂量时，系统在整个温区显示半导体型导电特征，而当掺杂量超过0.14时，系统发生由半导体到金属的转变，且转变的温度随掺杂量增加而移向高温瑞．基于对实验结果的分析，就Ca位上Ba掺杂所起的作用进行了初步探讨．
A series of La0.5Ca0.5-xBaxMnO3 samples with single phase structure were prepared by solid-state reaction. Their structures changed from cubic system to typical orthorhombic system with the increase of Ba content. Experiments at zero field show that at lower doping levels, the system exhibits semiconductor-type conductivity throughout the temperature range, whereas when the doping level exceeds 0.14, the transition from semiconductor to metal occurs and the transition temperature With the increase of doping to high temperature Rui. Based on the analysis of the experimental results, the effect of Ba doping on Ca site was discussed.