Amorphous-like thermal conductivity and high mechanical stability of cyclopentane clathrate hydrate.

The thermal conductivity of cyclopentane clathrate hydrate (CP CH) of type II was measured at temperatures down to 100 K and at pressures up to 1.3 GPa. The results show that CP CH displays amorphous-like characteristic of many crystalline clathrate hydrates, , tetrahydrofuran (THF) CH.

Neutron scattering study of polyamorphic THF·17(HO) - toward a generalized picture of amorphous states and structures derived from clathrate hydrates.

From crystalline tetrahydrofuran clathrate hydrate, THF-CH (THF·17HO, cubic structure II), three distinct polyamorphs can be derived. First, THF-CH undergoes pressure-induced amorphization when pressurized to 1.3 GPa in the temperature range 77-140 K to a form which, in analogy to pure ice, may be called high-density amorphous (HDA).

Evidence suggesting kinetic unfreezing of water mobility in two distinct processes in pressure-amorphized clathrate hydrates.

Type II clathrate hydrates (CHs) with tetrahydrofuran (THF), cyclobutanone (CB) or 1,3-dioxolane (DXL) guest molecules collapse to an amorphous state near 1 GPa on pressurization below 140 K. On subsequent heating in the 0.2-0.

Structural investigation of three distinct amorphous forms of Ar hydrate.

Three amorphous forms of Ar hydrate were produced using the crystalline clathrate hydrate Ar·6.5HO (structure II, 3̄, ≈ 17.1 Å) as a precursor and structurally characterized by a combination of isotope substitution (Ar) neutron diffraction and molecular dynamics (MD) simulations.

Layered Zinc Hydroxide Dihydrate, Zn(OH)·2HO, from Hydrothermal Conversion of ε-Zn(OH) at Gigapascal Pressures and its Transformation to Nanocrystalline ZnO.

Layered zinc hydroxides (LZHs) with the general formula (Zn) (OH) (A ) ·HO (A = Cl, NO , ac, SO , etc) are considered as useful precursors for the fabrication of functional ZnO nanostructures. Here, we report the synthesis and structure characterization of the hitherto unknown "binary" representative of the LZH compound family, Zn(OH)·2HO, with A = OH, = 5, = 2, and = 2. Zn(OH)·2HO was afforded quantitatively by pressurizing mixtures of ε-Zn(OH) (wulfingite) and water to 1-2 GPa and applying slightly elevated temperatures, 100-200 °C.

Transitions in pressure-amorphized clathrate hydrates akin to those of amorphous ices.

Type II clathrate hydrates (CHs) were studied by thermal and dielectric measurements. All CHs amorphize, or collapse, on pressurization to 1.3 GPa below 135 K.

Elucidation of the pressure induced amorphization of tetrahydrofuran clathrate hydrate.

The type II clathrate hydrate (CH) THF·17 HO (THF = tetrahydrofuran) is known to amorphize on pressurization to ∼1.3 GPa in the temperature range 77-140 K. This seems to be related to the pressure induced amorphization (PIA) of hexagonal ice to high density amorphous (HDA) ice.