2007/05/21 by Antonio M. Puertas, Cristiano De Michele, Francesco Sciortino +2 · 40 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Atomic packing factor #Brownian dynamics #Brownian motion #Colloid #Divergence (linguistics) #Material Dynamics and Properties #Newtonian fluid #Phase Equilibria and Thermodynamics #Viscoelasticity #Viscosity #cond-mat.soft
paper · pdf · doi:10.1063/1.2772628
published in The Journal of Chemical Physics 127(14), 144906 (American Institute of Physics) · 12 pages; sent to J. Chem. Phys
arxiv created 2007/05/21 · openalex publication_date 2007/10/09 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report a numerical investigation of the viscoelastic behavior in models for steric repulsive and short-ranged attractive colloidal suspensions, along different paths in the attraction strength vs packing fraction plane. More specifically, we study the behavior of the viscosity (and its frequency dependence) on approaching the repulsive glass, the attractive glass, and in the reentrant region where viscosity shows a nonmonotonic behavior on increasing attraction strength. On approaching the glass lines, the increase of the viscosity is consistent with a power-law divergence with the same exponent and critical packing fraction previously obtained for the divergence of the density fluctuations. Based on mode-coupling calculations, we associate the increase of the viscosity with specific contributions from different length scales. We also show that the results are independent of the microscopic dynamics by comparing Newtonian and Brownian simulations for the same model. Finally, we evaluate the Stokes-Einstein relation approaching both glass transitions, finding a clear breakdown which is particularly strong for the case of the attractive glass.