We present inelastic neutron scattering measurements on liquid mercury at room temperature for wave numbers q in the range 0.3 <q< 7.0 \AA−1. We find that the energy halfwidth of the incoherent part of the dynamic structure factor S(q,E) is determinded by a self-diffusion process. The halfwidth of the coherent part of S(q,E) shows the characteristic behavior expected for a cage diffusion process. We also show that the response function at small wave numbers exhibits a quasi-elastic mode with a time scale characteristic of cage diffusion, however, its intensity is larger by an order of magnitude than what would be expected for cage diffusion. We speculate on a scenario in which the intensity of the cage diffusion mode at small wave numbers is amplified through a valence fluctuation mechanism.
@article{arxiv.cond-mat/0307481,
title = {Cage diffusion in liquid mercury},
author = {Y. S. Badyal and U. Bafile and K. Miyazaki and I. M. de Schepper and W. Montfrooij},
journal= {arXiv preprint arXiv:cond-mat/0307481},
year = {2016}
}