Ca2KNa（PO4）2结构的大角度XRD测定

通过大角度的粉末X射线衍射测定了正磷酸钠钾钙[(Ca2KNa(PO4)2)]晶体陶瓷的晶格参数，分析化学纯度的碳酸钙，磷酸二氢钾、磷酸二氢钠按照2：1：1的摩尔比混合后于1300摄氏度高温反应4h，得到了组合符合Ca2KNa(PO4)2的正磷酸钠钾钙陶瓷，在10度－130度的2θ扫描角范围内，在室温下进行粉末X射线衍射。测定结果显示，高温合成的Ca2KN2(PO4)2晶体相是α－CaKPO4和α－CaNaPO4晶体的高温固溶体，呈六方晶体结构，晶格参数为：α0＝0．54396nm,C0=0.72976nm，晶胞体积V＝0．187nm^3.

StructureDetermination of Ca2KNa(PO4)2 with Wide-angle XRD

The lattice constants of crystalline calcium potassium sodium orthophosphate [Ca2KNa(PO4)2] were investigated with wide-angle powder X-ray diffraction (XRD) method. The Ca2KNa(PO4)2 ceramic was synthesized by solid state reaction of calcium carbonate, potassium dihydrogen phosphate and sodium dihydrogen phosphate dihydrate in 2/1/1 molar ratio at 1 300(C for 4 h. Over the 2θ range of 10°～130°, the powder XRD was performed at room temperature. A hexagonal lattice with the parameters a0=0.54393nm, c0=0.72976nm and a cell volume of V=0.187nm3 were determined for the high temperature phase of Ca2KNa(PO4)2. The crystal phase is just a solid-solution of α-CaKPO4 and α-CaNaPO4, and the lattice parameters are between that of CaNaPO4 and CaKPO4 formed at high temperature.