概括
高压可逆地破坏了酸盐玻璃中的四面体协调,改变了和离子环境. 这解释了行星科学和地幔酸盐的观测.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 矿物物理 矿物物理
背景情况:
- 在环境条件下,酸盐玻璃表现出和离子的四面体协调.
- 了解极端压力下的协调变化对于行星科学至关重要.
研究的目的:
- 在高压下研究和在酸盐玻璃中的协调状态.
- 为了确定压力诱导的协调变化是否可逆.
主要方法:
- 红外光谱学被用来分析SiO(2),CaMgSi(2) O(6) 和CaAlSi(2) O(8) 的眼镜.
- 实验是在20千兆帕斯卡尔以上的压力和室温下进行的.
主要成果:
- 四面体协调在20千兆帕斯卡以上被严重破坏.
- 和的协调数量逐渐增加,混合环境 (四倍至六倍) 观察到高达40千兆帕斯卡.
- 在减压到室温时,协调变化是可逆的.
结论:
- 高压会导致无形酸盐协调的持续和可逆变化.
- 这种现象解释了在灭的玻璃和地幔酸盐的浅融坡上没有观察到的协调变化.
- 可逆的协调变化可能会导致陆地行星中的中性浮力岩石.
相关概念视频
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In IR spectroscopy of carboxylic acids, the C=O bond shows a characteristic band between 1710 and 1760 cm⁻¹, and the O–H bond exhibits a broad band between 2500 and 3300 cm⁻¹.
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency, 1710 cm−1. The C=O bond of the...
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