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arXiv · 1709.07648

Hydrogen mean force and anharmonicity in polycrystalline and amorphous ice

Alexandra Parmentier·Carla Andreani·Giovanni Romanelli·Jacob J. Shephard·Christoph G. Salzmann·Roberto Senesi
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Abstract

The hydrogen mean force from experimental neutron Compton profiles is derived using deep inelastic neutron scattering on amorphous and polycrystalline ice. The formalism of mean force is extended to probe its sensitivity to anharmonicity in the hydrogen-nucleus effective potential. The shape of the mean force for amorphous and polycrystalline ice is primarily determined by the anisotropy of the underlying quasi-harmonic effective potential. The data from amorphous ice show an additional curvature reflecting the more pronounced anharmonicity of the effective potential with respect to that of ice Ih.

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Alexandra Parmentier, Carla Andreani, Giovanni Romanelli, Jacob J. Shephard, Christoph G. Salzmann, Roberto Senesi. 2017-09-22. Hydrogen mean force and anharmonicity in polycrystalline and amorphous ice. https://doi.org/10.1007/s11467-017-0724-4

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