Transformations in methane hydrates

I‐Ming Chou

doi:10.1073/pnas.250466497

Transformations in methane hydrates

2000-11-21

179

OA

AI

Alexander F. Goncharov

DOI：10.1073/pnas.250466497

原文链接

查看原文

摘要

En 中文

Detailed study of pure methane hydrate in a diamond cell with in situ optical, Raman, and x-ray microprobe techniques reveals two previously unknown structures, structure II and structure H, at high pressures. The structure Il methane hydrate at 250 MPa has a cubic unit cell of a = 17.158(2) Angstrom and volume V = 5051.3(13) Angstrom (3); structure H at 600 MPa has a hexagonal unit cell of a = 11.980(2) A, c = 9.992(3) Angstrom, and V = 1241.9(5) Angstrom (3). The compositions of these two investigated phases are still not known. With the effects of pressure and the presence of other gases in the structure, the structure Ii phase is likely to dominate over the known structure I methane hydrate within deep hydrate-bearing sediments underlying continental margins.

Keyword:

HIGH-PRESSURE PHASE

DIAMOND-ANVIL CELL

X-RAY-DIFFRACTION

CLATHRATE HYDRATE

ICE

SYSTEM

GAS

Transformations in methane hydrates

摘要

AI总结

期刊

机构