New members of La326 type compounds La2Ca1-xNaxCu2O6-δ, La2-xSrxCa0.7Na0.3Cu2O6-δ, La2-xKxCaCu2O6-δ, and La1.6K0.4Ca1-xSrxCu2O6-δ were prepared with solid state reaction. Experiments show that calcination and sinter temperatures as well as the heating rate used to prepare single phase La326 type compounds substituted with sodium and potassium are lower than those used to prepare Ln2-xA1-xCu2O6-δ (A = Ca, Sr). Their structures were verified with Rietveld refinement to belong to the structure type of typical La326 type compounds La2-xA1-xCu2O6-δ (A = Ca, Sr). The D.C. magnetic susceptibility dependence of the temperature of the La1.7Sr0.3Ca0.7Na0.3Cu2O5.86 sample shows that the sample displays a diamagnetic signal at 63 K.
Tao, F., Zhou, X. J., Che, G. C., Xu, J. H., Zhu, S. F., & Zhao, B. J. (2000). New La326 type compounds substituted with sodium and potassium. Journal of Alloys and Compounds, 296(1–2), 46–52. https://doi.org/10.1016/S0925-8388(99)00241-8