# Depletion potentials in colloidal mixtures of spheres and rods

@article{Roth2003DepletionPI, title={Depletion potentials in colloidal mixtures of spheres and rods}, author={Roland Roth}, journal={Journal of Physics: Condensed Matter}, year={2003}, volume={15} }

We calculate the depletion potential between two hard spheres of radii Rs and that between one hard sphere and a planar hard wall in a sea of hard rigid spherocylindrical rods of length L and radius Rr. Unlike earlier studies our approach takes into account the true geometry of the problem and gives, to first order in the rod density, the exact depletion potential for all values of Rs, L, and Rr.

## 27 Citations

Depletion potentials in colloidal mixtures of hard spheres and rods.

- PhysicsThe Journal of chemical physics
- 2008

The comparison between the results and those of other theories suggests that the acceptance ratio method is the only efficient method used to compute the depletion potential induced by nonspherical colloids with the volume fraction beyond the ideal-gas approximation.

Depletion potential in colloidal mixtures of hard spheres and platelets.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2004

The depletion potential between two hard spheres in a solvent of thin hard disclike platelets is investigated by using either the Derjaguin approximation or density functional theory, which yields nearly exact results for the bulk properties of the hard-platelet fluid at densities two times smaller than the density of the isotropic fluid at isotropics-nematic phase coexistence.

Direct measurement of entropic forces induced by rigid rods.

- Biology, PhysicsPhysical review letters
- 2003

The first direct depletion potential measurements for a single colloidal sphere close to a wall in a suspension of rigid colloidal rods are presented, and a density functional theory approach is developed that accurately accounts for this experimental situation.

Simulation and theory of fluid-fluid interfaces in binary mixtures of hard spheres and hard rods

- Physics
- 2003

We consider the free interface between demixed fluid phases in a mixture of hard spheres and vanishingly thin hard rods using Monte Carlo simulations and density functional theory. Both approaches…

Entropic forces in dilute colloidal systems.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2006

This paper systematically studies the form in which concentration and geometry determine the entropic interaction between colloidal particles in a large variety of dilute colloidal systems composed of spherical and nonspherical hard particles.

A reference interaction site model approach to depletion forces induced by hard rodlike particles.

- PhysicsThe Journal of chemical physics
- 2005

We study the effective interactions among large hard spherical colloidal particles induced by small hard rodlike particles and compare them with those induced by small hard spherical particles to…

Phase stability of colloidal mixtures of spheres and rods.

- Materials Science, PhysicsThe Journal of chemical physics
- 2021

Good correspondence is found between the experimental phase transitions and the theoretical FVT model where the excluded volume of the rod-like depletants was explicitly accounted for in both the reservoir and the system.

Entropic forces and directed alignment of hard squares in suspensions of rods and disks.

- PhysicsThe Journal of chemical physics
- 2010

Monte Carlo simulations in two dimensions are used to study the depletion forces between two hard squares in a suspension of hard rods or disks and observe rich behavior, in which the relative orientation depends on the size, concentration, and shape of the depletion agent.

Effective potential between two spheres in a suspension of adhesive rods.

- Materials SciencePhysical review. E, Statistical, nonlinear, and soft matter physics
- 2007

Analytic treatment and Monte Carlo simulations are used to study the effective potential between two spheres in a suspension of rods whose ends can adhere to the surface of the spheres and the results are qualitatively consistent with a recent experimental work.

The depletion potential in one, two and three dimensions

- Physics
- 2005

We study the behavior of the depletion potential in binary mixtures of hard particles in one, two, and three dimensions within the framework of a general theory for depletion potential using density…

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