RT Journal Article
T1 Microrheology of colloidal suspensions via dynamic Monte Carlo simulations
A1 García Daza, Fabián A.
A1 Puertas, Antonio M.
A1 Cuetos, Alejandro
A1 Patti, Alessandro
K1 Simulations of colloids
K1 Microrheology
K1 Dynamic Monte Carlo
K1 Brownian motion
AB Understanding the rheology of colloidal suspensions is crucial in the formulation of a wide selection of industry-relevant products, such as paints, foods and inks. To characterise the viscoelastic behaviour of these soft materials, one can analyse the microscopic dynamics of colloidal tracers diffusing through the host fluid and generating local deformations and stresses. This technique, referred to as microrheology, links the bulk rheology of fluids to the microscopic dynamics at the particle scale. If tracers are subjected to external forces, rather than freely diffusing, it is called active microrheology. Motivated by the impact of microrheology in providing information on local structure in complex systems such as colloidal glasses, active matter or biological systems, we have extended the dynamic Monte Carlo (DMC) technique to investigate active microrheology in colloidal suspensions. The original DMC theoretical framework, able to accurately describe the Brownian dynamics of colloids at equilibrium, is here reconsidered and expanded to describe the effects of an external force pulling a tracer embedded in isotropic colloidal suspensions at different densities. To this end, we studied the dynamics of a spherical tracer dragged by a constant external force through a bath of spherical and rod-like particles of comparable size. We could extract valuable details on its effective friction coefficient, being constant at small and large values of the external force, but otherwise displaying a nonlinear behaviour that indicates the occurrence of a force-thinning regime. Our DMC simulation results are in excellent quantitative agreement with past Langevin dynamics simulations and theoretical works for the bath of spherical colloids. The bath of rod-like particles is studied in the isotropic phase, and displays an example where DMC is more convenient than Brownian or Langevin dynamics, in this case, in dealing with particle rotation.
PB Elsevier
YR 2021
FD 2021
LK https://hdl.handle.net/10433/25827
UL https://hdl.handle.net/10433/25827
LA en
NO J. Colloid  Interface Sci. 605, 182-192 (2022)
NO Universidad Pablo de Olavide. Departamento de Sistemas Físicos, Químicos y Naturales
DS RIO
RD Apr 28, 2026