The pyrite-type high-pressure form of silica
The pyrite-type high-pressure form of silica
复制标题
DOI：
10.1126/science.1114879
复制
发表时间：
2005-08-05
期刊：
影响因子：
56.9
通讯作者：
Ohishi, Y
中科院分区：
文献类型：
--
作者：
Kuwayama, Y;Hirose, K;Ohishi, Y
二氧化硅 (SiO2) 在高压下表现出广泛的多晶型。 X 射线衍射测量表明，具有黄铁矿型结构的高压形式比其他已知的二氧化硅相更致密，在 268 吉帕斯卡和 1800 开尔文以上稳定。硅配位数从α-PbO2型相中的6增加到黄铁矿型相中的6+2，导致相变时密度大幅增加约5%。
Silica (SiO2) exhibits extensive polymorphism at elevated pressures. X-ray diffraction measurements showed that a high-pressure form with a pyrite-type structure, denser than other known silica phases, is stable above 268 gigapascals and 1800 kelvin. The silicon coordination number increases from 6 in the alpha-PbO2-type phase to 6+2 in the pyrite-type phase, leading to a large increase in density by about 5% at the phase transition.