Figure 2. Mean square displacements (MSD) on the nanosecond timescale of H30S-3 M NaCl (circles), H30S-3 M KCl (squares) and H50S-3 M NaCl (triangles) extracted from elastic intensities in the wave-vector range 0.34–0.85 A⁻¹.

The solid lines represent the best fits for data above 270 K (see text), while the dashed line corresponds to the MSD at the reference value of 37 °C. A steeper slope with temperature indicates a softer effective force constant for the motions (see text).