概括
高压将 (Si) 转化为酸盐液体,改变其局部几何形状. 这项研究使用 (29) Si NMR检测了Si协调的压力诱导变化,揭示了在无形阶段向八面体Si的转变.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 酸盐液体中 (Si) 离子体的协调和局部几何学对于岩性质至关重要.
- 了解这些压力下的结构变化对于地质化学和材料科学至关重要.
研究的目的:
- 为了研究在酸盐玻璃中压力诱导的Si协调变化.
- 描述Si在高压下无形相中的局部原子结构.
主要方法:
- 使用 (29) Si 魔力角旋转核磁共振 (MAS NMR) 谱法.
- 在高压 (8 GPa) 和高温 (1500 °C) 中灭玻璃样本中分析了二氧化 (Na(2) Si(2) O(5).
主要成果:
- 检测到约1.5%的八面体Si存在于从8GPa和1500°C灭的玻璃中.
- 证实八面体Si是同质无形相的一部分.
- 观察到占主导地位的四面体Si物种的不成比例,以增加压力,使桥梁和非桥梁氧气的分布更加随机.
结论:
- 在酸盐玻璃中,高压会诱导Si协调的转变.
- 观察到的结构变化影响了氧物种在离子周围的分布.
- 这些发现为在极端条件下酸盐液体的行为提供了洞察力.
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