- 2:36 PM

On the Use of Entropy-Scaling to Describe Dynamic Properties of Water

Ravi Chopra1, Thomas M. Truskett2, and Jeffrey R. Errington1. (1) Chemical and Biological Engineering, University at Buffalo, 814 Furnas Hall, Buffalo, NY 14260, (2) Department of Chemical Engineering and Institute for Theoretical Chemistry, The University of Texas at Austin, 1 University Station, C0400, Austin, TX 78712

Transport coefficients such as the diffusivity, viscosity, and thermal conductivity are important quantities for both scientific research and engineering design. Empirical scaling relationships have emerged as a promising approach for predicting such quantities. In fact, recent studies have demonstrated that entropy-scaling relations provide a robust means to describe the dynamics of bulk and confined atomistic fluids. In this work we examine the extent to which these ideas can be used to characterize molecular fluids. Through the use of molecular dynamics and transition-matrix Monte Carlo simulations we study relationships between transport (translational and rotational diffusivity, characteristic relaxation times), thermodynamic (excess entropy), and structural (two-body excess entropy) properties of the extended simple point charge water model. Calculations are performed over a broad range of conditions that span from the supercooled liquid regime to the critical region. Our results suggest that entropy-scaling relations could serve as a powerful means for predicting transport properties of molecular fluids.