性,和甲酸盐玻璃的结构
Henrik Bradtmüller1,2, Esther Girón Lange3,4, Anita Zeidler3
1Instituto de Física de São Carlos, Universidade de São Paulo, IFSC-USP, 13566-590 São Carlos, SP, Brazil.
The Journal of chemical physics
|November 24, 2025
概括
这项研究使用先进技术研究了金属酸盐玻璃. 发现四个协调的和离子没有形成玻璃网络结构.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 玻璃科学 玻璃科学
背景情况:
- 金酸盐玻璃在各种应用中至关重要.
- 了解 (Mg2+, Zn2+) 在酸盐网络中的作用,是定制玻璃特性的关键.
- 之前的研究对离子协调和网络形成产生了相互矛盾的结果.
研究的目的:
- 为了阐明二价 (Mg2+, Zn2+) 在金属酸盐玻璃中的结构作用.
- 确定离子体的协调状态及其对酸盐网络聚合物的影响.
- 为了研究阴离子协调和NMR化学转移之间的关系.
主要方法:
- 结合中子和高能X射线衍射.
- 拉曼光谱法 拉曼光谱法
- 固态29Si和25Mg神奇角度旋转 (MAS) 核磁共振 (NMR) 光谱,包括旋转器辅助的群体转移.
主要成果:
- 衍射揭示了大多数含和的玻璃中四个协调的Mg2+和Zn2+离子的显著数量.
- 29Si NMR显示不同程度的酸盐网络聚合.
- 拉曼光谱学支持了NMR的发现.
- 没有证据表明四协调的Mg2+和Zn2+具有形成网络的作用.
- 没有观察到Mg-O协调数 (衍射) 和25Mg MAS NMR化学转移之间的明显相关性.
结论:
- 这些金属酸盐玻璃中的四坐标的Mg2+和Zn2+离子不起网络形成者的作用.
- 这些离子体的结构行为很复杂,不仅仅是由协调号决定的.
- 需要进一步的研究才能充分理解阴离子玻璃网络的相互作用.
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