石英型晶体和玻璃态GeO₂在压力下的结构变化

Structural changes of quartz-type crystalline and vitreous GeO2 under pressure.

作者信息

Ohtaka O, Yoshiasa A, Fukui H, Murai K I, Okube M, Katayama Y, Utsumi W, Nishihata Y

机构信息

Earth and Space Science, Osaka University, Toyonaka, Japan.

出版信息

J Synchrotron Radiat. 2001 Mar 1;8(Pt 2):791-3. doi: 10.1107/s0909049500018306.

DOI:10.1107/s0909049500018306

PMID:11512933

Abstract

Using a large volume high pressure apparatus, quartz-type crystalline GeO2 and Li2O-4GeO2 glass have been compressed up to 14 GPa at room temperature and their local structural changes have been investigated by an in-situ XAFS method. In quartz-type crystalline GeO2, the change of the coordination number from 4 to 6 begins above 8 GPa and finishes below 12 GPa. On decompression, reversal transition begins below 8 GPa and there is a large hysteresis. Almost no sixfold coordination of Ge is preserved after releasing pressure. Change of coordination number in vitreous Li2O-4GeO2 begins above 6 GPa and is completed below 10 GPa. Reversal transition begins below 10 GPa and the hysteresis is smaller than that of quartz-type GeO2. Change of coordination number in vitreous Li2O-4GeO2 is also reversal.

摘要

使用大体积高压装置，在室温下将石英型晶体GeO₂和Li₂O - 4GeO₂玻璃压缩至14 GPa，并通过原位XAFS方法研究了它们的局部结构变化。在石英型晶体GeO₂中，配位数从4变为6的变化在8 GPa以上开始，在12 GPa以下完成。解压时，反转转变在8 GPa以下开始，并且存在较大的滞后现象。释放压力后，几乎没有保留Ge的六重配位。玻璃态Li₂O - 4GeO₂中配位数的变化在6 GPa以上开始，在10 GPa以下完成。反转转变在10 GPa以下开始，并且滞后现象比石英型GeO₂的小。玻璃态Li₂O - 4GeO₂中配位数的变化也是可逆的。