高压下α-石英和柯石英的相变行为  

Phase Transitions of α-Quartz and Coesite at High Pressures

作　　者：吴也 陈星 黄海军[1] WU Ye;CHEN Xing;HUANG Haijun(School of Science,Wuhan University of Technology,Wuhan 430070,Hubei,China)

机构地区：[1]武汉理工大学理学院,湖北武汉430070

出　　处：《高压物理学报》2021年第1期10-17,共8页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(41602036);中央高校基本科研业务费专项资金(2019IA002)。

摘　　要：利用金刚石压腔和同步辐射X射线衍射技术,对α-石英和柯石英在常温高压下的相变行为进行了研究。实验结果表明:α-石英在约23 GPa开始发生结构相变,在约44 GPa相变完成,直至59 GPa仍能观察到结晶态;柯石英在约22 GPa转变为柯石英-Ⅱ相,高于36 GPa时,继续发生结构转变,直至59 GPa仍有结晶态;氖气和氩气所提供的不同静水压条件对α-石英和柯石英的高压相变行为影响不大。实验结果为进一步厘清二氧化硅物相的压致相变行为和相变机制提供了实验支撑。Phase behaviors ofα-quartz and coesite at high pressures and room temperature have been investigated by using diamond anvil cells combined with synchrotron X-ray diffraction.α-quartz undergoes a phase transition to a new phase at about 23 GPa,and the phase transition gets finished at about 44 GPa.The high-pressure phase of α-quartz can be observed up to 59 GPa.Coesite transforms to coesite-Ⅱ at about 22 GPa,and coesite-Ⅱ undergoes phase transitions above about 36 GPa.Crystalline phase can be observed up to 59 GPa in coesite.Different hydrostatic conditions provided by neon and argon have no crucial effect on high-pressure phase behaviors of α-quartz and coesite.These results not only clarify pressure-induced phase transition pathway of α-quartz and coesite,but also shed light on the transition mechanism of silica under high pressure.

关 键 词：α-石英 柯石英 金刚石压腔 相变 

分 类 号：O521.2[理学—高压高温物理]