Temperature dependence of diffusion properties of soft sticky dipole water

Abstract

The isobaric diffusivities for the soft sticky dipole water model between 230 and 330 K were studied in molecular dynamics simulations using Ewald summations for the long-range interactions. This simple single-point, angularly dependent model with parameters optimized at room temperature reproduces the experimental diffusion rates over a wide range of temperatures better than multi-point models. Its ability to reproduce the unusual temperature dependence of the diffusivities of supercooled water indicates the tetrahedral nature of water is important. Moreover, comparisons with other models indicate more tetrahedral potentials correlate with increasing the so-called Angell critical temperature and decreasing power of the temperature dependence.