Synchrotron radiation studies on pressure-induced structural changes in liquids and glasses
Synchrotron radiation studies on pressure-induced structural changes in liquids and glasses
复制标题
压力引起的液体和玻璃结构变化的同步辐射研究
DOI：
10.1088/0953-8984/15/1/347
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Y. Inamura
中科院分区：
文献类型：
--
作者：
Y. Katayama;Y. Inamura
同步辐射光源和大容量压力机的组合使我们能够在高达几吉帕斯卡的高压和1200摄氏度以上的高温下对液体和玻璃的结构变化进行原位观察。在这份报告中，我们提出了两个例子：液体锡和二氧化硅玻璃。在2.0和5.3 GPa下对液态Sn进行了X射线衍射测量。随着压力的增加，结构因子中第一峰的肩部变得不那么突出，第二峰与第一峰的位置的比率减小。这些变化归因于保持在液态的共价结构的减少。SiO2玻璃的X射线衍射的温度依赖性的数据进行了测量，高达560 ℃，17 GPa。样品在560 ℃以上结晶为硅镁石。虽然没有观察到剧烈的变化，在短程顺序，第一个尖锐的衍射峰的位置移动到更高的波数和尖锐的，它被观察到随着温度的升高。移动和锐化表明在中程秩序的一些放松。
Combination of synchrotron radiation sources and large-volume presses enables us to carry out in situ observations of structural change in liquids and glasses at high pressures up to several gigaPascals and high temperatures above 1200oC. In this report, we present two examples: liquid Sn and SiO2 glass. X-ray diffraction measurements were carried out on liquid Sn at 2.0 and 5.3 GPa. With increasing pressure, a shoulder of the first peak in the structure factor became less prominent and the ratio of the position of the second peak to that of the first peak decreased. These changes are attributed to a diminishing of the covalent structures remaining in the liquid state. Data on the temperature dependence of the x-ray diffraction by SiO2 glass were measured up to 560oC at 17 GPa. The sample crystallized to stishovite above 560oC. While no drastic change was observed in the short-range order, a shift of the position of the first sharp diffraction peak to higher wavenumber and a sharpening of it were observed with increasing temperature. The shift and the sharpening suggest some relaxation in the intermediate-range order.