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本文研究了含镧氟锆酸盐玻璃的形成区和晶化机理,并对该系统玻璃结构作了探讨。LaF_3的引入使玻璃形成能力增加。在PbF_2-LaF_3-ZrF_4三元系统或PbF_2-LaF_3-AlF_3-ZrF_4四元系统玻璃中均呈现分相现象,后者导致玻璃整体析晶。X-射线衍射的研究表明,在较低温度时,析出的晶相为PbF_2·ZrF_4,而在较高温度时,析出第二相LaF_3·2ZrF_4。La~(3+)在玻璃中的配位状态为[LaF_8],与[ZrF_6]、[ZrF_7]、[ZrF_8]、[AlF_6]等配位多面体通过共顶或共棱形成玻璃网络。随LaF_3和AlF_3含量的增加,Zr-F-Zr键角有增大的趋势。
In this paper, the formation of lanthanum fluorozirconate glasses and crystallization mechanism, and the glass structure of the system are discussed. The introduction of LaF_3 increases the glass-forming ability. In the PbF_2-LaF_3-ZrF_4 ternary system or PbF_2-LaF_3-AlF_3-ZrF_4 quaternary system glass phase separation phenomenon, which led to the overall crystallization of glass. X-ray diffraction shows that at lower temperature, the precipitated crystal phase is PbF 2 · ZrF 4, whereas at higher temperature, the second phase LaF 3 · 2 ZrF 4 is precipitated. The coordination state of La ~ (3+) in glass is [LaF_8], and the coordination polyhedron with [ZrF_6], [ZrF_7], [ZrF_8] and [AlF_6] forms a glass network by co- With the increase of the content of LaF_3 and AlF_3, the bond angle of Zr-F-Zr tends to increase.