New Type of Phase Transformation in Gas Hydrate Forming System at High Pressures. Some Experimental and Computational Investigations of Clathrate Hydrates Formed in the SF<sub>6</sub>−H<sub>2</sub>O System
作者:Aladko、A. I. Ancharov、S. V. Goryainov、A. V. Kurnosov、E. G. Larionov、Likhacheva、Manakov、V. A. Potemkin、M. A. Sheromov、A. E. Teplykh、V. I. Voronin、F. V. Zhurko
DOI:10.1021/jp061698r
日期:2006.10.1
hydrates, which is related to the existence of two different isostructural phases of the sulfur hexafluoride clathrate hydrates. Each of these phases has its own stability field on the phase diagram. The difference between these hydrates consists of partial filling of small D cages by SF(6) molecules in the high-pressure phase; at 900 MPa, about half of small cages are occupied. Our calculations indicate
在这项工作中,我们提出了一种高压气体水合物中一种新的,以前未知的结构转变类型,这与六氟化硫笼形水合物水合物的两个不同的同构相的存在有关。这些阶段中的每一个在阶段图上都有其自己的稳定性字段。这些水合物之间的区别在于,高压相中的SF(6)分子部分填充了小的D笼。在900 MPa下,约有一半的小笼子被占用。我们的计算表明,不可能增加小腔体的数量,因此,在任何压力值下,一部分腔体仍然空着,堆积密度相对较低。这个事实使我们可以假设在该系统中存在水合物形成的上限压力。