Discrete thermal patterns of hydrogen and deuterium molecules enclathrated in confined hydrate cages

Abstract

A clear understanding of guest dynamic behavior occurring in solely confined nanosized cages has often been achieved through the neutron diffraction technique. However, the incoherent scattering exhibited by hydrogen generates a background signal that makes it difficult to detect the coherent Bragg scattering from the sample. Without resort to deuteration, the direct usage of H-2 gas confined in a cage without a chemical bond was successfully performed, showing stable backgrounds through the incoherent scattering length of the H-2. In particular, the discrete thermal patterns of H-2 and D-2 in a THF hydrate system in terms of the difference in the physical properties of H and D were observed, revealing the completely different dissociation behavior between H-2 + THF and D-2 + THF clathrate hydrates under varying temperatures.