On the anomalous behaviour of microscopic diffusion of liquid water

We propose here a new interpretation of recent quasi-elastic neutron scattering (QENS) measurements on water. A line-shape analysis based on a stretched exponential ansatz for the time decay of density fluctuations enabled us to observe an anomalous dependence on the exchanged momentum of relevant relaxation parameters. We discuss this effect and relate it to an a priori uncorrelated anomaly, previously evidenced by diffraction measurements.