Dynamics of hydrogen guests in ice XVII nanopores
arXiv:1706.09350 · doi:10.1103/PhysRevMaterials.1.065602
Abstract
The present high-resolution inelastic neutron scattering experiment on ice XVII, containing molecular hydrogen with different ortho/para ratio, allows to assign the H motion spectral bands to rotational and center-of-mass translational transitions of either {\it para}- or {\it ortho}-H. Due to its structure, ice XVII confines H molecules to move in spiral channels of molecular size. Reported data demonstrate that H molecules rotate almost freely in these nanometric channels, though showing larger perturbation than in clathrate hydrates, and perform a translational motion exhibiting two low frequency excitations. The good agreement between experimental spectra and corresponding molecular dynamics results clearly enables to portray a picture of the confined motions of a hydrophobic guest within a metastable ice framework, i.e. ice XVII.
5 pages, 4 figures