Clathrate and semi-clathrate hydrates have recently been gaining major interest as hydrogen storage material. The benefits of hydrates, such reversible formation dissociation, their environmentally friendly nature, economical costs, lower fire risk, make them one the most promising materials. One challenges when storing in hydrate crystals is extreme pressure temperature conditions required for...

The performance of local correlation methods is examined for the interactions present in clusters of bromine with water where the combined effect of hydrogen bonding (HB), halogen bonding (XB), and hydrogen-halogen (HX) interactions lead to many interesting properties. Local methods reproduce all the subtleties involved such as many-body effects and dispersion contributions provided that specif...

The cause of a large increase of atmospheric methane concentration during the Younger Dryas-Preboreal abrupt climatic transition (approximately 11,600 years ago) has been the subject of much debate. The carbon-14 (14C) content of methane (14CH4) should distinguish between wetland and clathrate contributions to this increase. We present measurements of 14CH4 in glacial ice, targeting this transi...

A ternary type-I Si clathrate K(8)Ga(8)Si(38) has been revealed to be an indirect band gap semiconducting material with an energy gap (E(g)) of approximately 0.10 eV, which is much smaller than the calculated E(g) value that is 0.15 eV wider than E(g) of elemental Si with the diamond-type structure.

We review the reservoirs of methane clathrates that may exist in the different bodies of the Solar System. Methane was formed in the interstellar medium prior to having been embedded in the protosolar nebula gas phase. This molecule was subsequently trapped in clathrates that formed from crystalline water ice during the cooling of the disk and incorporated in this form into the building blocks ...

In addition to their importance as abundant hydrocarbon deposits in nature, clathrate hydrates are being studied as potential media for hydrogen and carbon dioxide storage and as "nano-reactors" for small molecules. However, little is known about the behavior of reactive species in such materials. We have employed muon spin spectroscopy to characterize various organic free radicals that reside ...

The reaction of dimethyl-amine hydro-chloride, 18-crown-6 and ferric chloride in ethanol yields the title compound, (C(2)H(8)N)[FeCl(4)]·C(12)H(24)O(6), which exhibits an unusual supramolecular structure. The protonated dimethyl-amine contains one NH(2) (+) group, resulting in a 1:1 supra-molecular rotator-stator structure (CH(3)-NH(2) (+)-CH(3))(18-crown-6), through N-H⋯O hydrogen-bonding inte...