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在玻璃酸玻璃中识别和量化酸环境:B NMR-峰值分配,辅助双量子实验

Baltzar Stevensson¹, Peng Lv^1,2, Mattias Edén¹

¹Physical Chemistry Division, Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm SE-106 91, Sweden.

The journal of physical chemistry. B

|December 10, 2024

概括

精确的11B神奇角度旋转的NMR光谱解卷揭示了酸盐在玻璃玻璃中的酸盐物种化. 分析澄清了B[3]和B[4]物种的联系,有助于结构理解.

科学领域:

材料科学材料科学材料科学
固态化学固态化学
频谱学是一种光谱学.

背景情况:

酸玻璃含有BO3 (B[3]) 和BO4 (B[4]) 网络组.
了解这些物种的物种化和联系对于玻璃性能至关重要.
以前的11B NMR研究提供了集成共振,限制了详细的物种化.

研究的目的:

为了探索精确的11B魔力角旋转 (MAS) 核磁共振光谱解卷,以在玻璃玻璃酸中进行详细的酸物种化.
对B[3]和B[4]物种的11B NMR峰值分配进行批判性审查和完善.
阐明不同协调环境和网络联系的结构起源.

主要方法:

11B 魔术角度旋转 (MAS) 核磁共振 (NMR) 光谱学.
11B MAS NMR光谱的光谱解卷,以量化B[3]和B[4]物种.
双量子-单量子 (2Q-1Q) 11B MAS 核磁共振实验用于探测 B-O-B 联系.
分析不同组成和网络修饰剂的玻璃酸盐系列.

主要成果:

核磁共振光谱解卷揭示了低NBO玻璃玻璃中的B[4]-O-Si连接的主导地位.
种类表现出对BO3种群和离子组成的显著依赖.
对于具有可比B和Si含量的眼镜,建议使用11B[4]光谱区域的三峰解卷度.
2Q-1Q 11B NMR区分了"环"B[3]单位 (Si-poor) 和"非环"B[3]单位 (Si-rich) 的区别.

结论:

精确的11B MAS NMR解卷提供了超越集成酸盐物种化的洞察力.
这项研究澄清了B[3]和B[4]的物种化及其联系 (例如,B[4]-O-Si,B[3]-O-Si).
在使用11B NMR分析富含NBO的酸盐玻璃中仍然存在挑战.

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