中文摘要：

本文应用金刚石压腔装置结合拉曼光谱分析技术原位观测了高温高压条件下水镁石的结构变化特征。结果表明：常温升至300℃过程中,随温度升高,水镁石中表征H-O对称伸缩振动的3652 cm-1拉曼特征峰向低波数移动,拉曼特征峰波数与对应的体系温度呈现良好的线性相关关系。常温条件下体系加压过程中,当压力升高至1.19 GPa时,水镁石中表征H-O振动的3652 cm-1拉曼峰向高波数移动并逐渐消失,同时产生表征方镁石的1078 cm-1拉曼特征峰,表明水镁石脱水相变为方镁石。随后压力降低过程中,表征水镁石H-O振动的3652 cm-1拉曼特征峰没有重新出现,脱水相变过程不可逆。

英文摘要：

In-situ observation of the structure property of brucite under the condition of high temperatures and pressures using Hydrothermal Diamond Anvil Cell and Raman spectrum technique was conducted.The results show that the H-O vibration of brucite at Raman peak 3652 cm-1 moved to lower wavenumbers at higher temperatures and there is a very good linear relationship between Raman peak wavenumbers and temperatures with the increasing temperatures from room temperatures to 300 ℃.During the process of increasing pressure to 1.19 GPa at room temperature,the H-O vibration of brucite at Raman peak of 3652 cm-1 becomes weaker and gradually disappears and 1078 cm-1 which is presented periclase is emerged,and the dehydration and phase transition happen and brucite changes to periclase.In the process of decreasing pressure,the brucite Raman peak of H-O vibration does not appear,which shows that the dehydration and phase transition are not reversible.