Exact evaluation of the depletion force between nanospheres in a polydisperse polymer fluid under Θ conditions.

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We analyze a system consisting of two spherical particles immersed in a polydispersed polymer solution under theta conditions. An exact theory is developed to describe the potential of mean force between the spheres for the case where the polymer molecular weight dispersity is described by the Schulz-Flory distribution. Exact results can be derived for the protein regime, where the sphere radius (Rs) is small compared to the average radius of gyration of the polymer (Rg). Numerical results are relatively easily obtained in the cases where the sphere radius is increased. We find that even when q = Rg/Rs⪆ 10, then the use of a monopole expansion for the polymer end-point distribution about the spheres is sufficient. For even larger spheres q ≈ 1, accuracy is maintained by including a dipolar correction. The implications of these findings on generating a full many-body effective interaction for a collection of N spheres imbedded in the polymer solution are discussed.


External organisations
  • University of New South Wales
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Theoretical Chemistry
Original languageEnglish
Article number194903
JournalJournal of Chemical Physics
Issue number19
Publication statusPublished - 2014
Publication categoryResearch

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)

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