采用固相化学反应方法成功合成了 GdY(WO4)3, Gd2(MoO4)3, DyGd(MoO4)3, DyTb(MoO4)3, 利用高、低温 X射线衍射方法对其结构及其晶胞参数随温度的变化进行了研究. 结果表明 GdY(WO4)3, Gd2(MoO4)3, DyGd(MoO4)3, DyTb(MoO4)3化合物的晶胞体积均随温度的升高而增大, 为正热膨胀系数材料.通过对其晶体结构进行认真分析并与负热膨胀系数材料 Sc2(WO4)3的结构 进行对比,认为这四种化合物分别属于α-d2(MoO4)3型和 CaWO4(白钨矿 )型的结构相: 其结构 相对致密,氧原子不再只是两配位,不满足产生负热膨胀必要的结构条件,因此所合成的材料没有 产生负热膨胀效应.
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