Coordination environment of fluorine in the CaO-SiO2-CaF2 glasses bearing Na2O:: A solid-state 19F MAS NMR study
Coordination environment of fluorine in the CaO-SiO2-CaF2 glasses bearing Na2O:: A solid-state 19F MAS NMR study
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DOI：
10.2355/isijinternational.44.1527
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发表时间：
2004-01-01
影响因子：
1.8
通讯作者：
Hayashi, S
中科院分区：
文献类型：
--
作者：
Hayashi, M;Watanabe, T;Hayashi, S
用F-19MAS核磁共振仪对CaO-SiO_2-CaF_2-Na_2O系玻璃中氟的配位环境进行了测定，确定了F-配位环境的组成依赖关系。对于n(Na)/(n(Na)+n(Ca))小于或等于0.3的样品，大多数F-与钙离子四配位，其中n表示每个阳离子的摩尔分数。另一方面，n(Na)(n(Na)+n(Ca))值大于或等于0.4的样品含有与Na+和Ca+配位的F-和由Na+配位的F-六配位。
The coordination environment of fluorine in the CaO-SiO2-CaF2-Na2O glasses has been measured by F-19 MAS NMR over a wide composition range including the similar compositions to those of mould fluxes so as to determine the composition dependence of the coordination environment of F-. Most of F- are fourfold-coordinated by Ca2+ for the samples having the value of n(Na)/(n(Na)+n(Ca))less than or equal to0.3, where n represents the mole fraction of each cation. On the other hand, the samples having the value of n(Na)(n(Na)+n(Ca))greater than or equal to0.4 contain F- coordinated with both Na+ and Ca+ and F- sixfold-coordinated by Na+.