Return
Transformations in methane hydrates
DOI:10.1073/pnas.250466497.png)
Abstract
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.
Keywords:
HIGH-PRESSURE PHASE
DIAMOND-ANVIL CELL
X-RAY-DIFFRACTION
CLATHRATE HYDRATE
ICE
SYSTEM
GAS
AI Summary
Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.
Journal
P
IF:
9.1
Papers:
10.8W
Citations:
73.5W
Organization
No organization information available

