How soft repulsion enhances the depletion mechanism
- Author(s)
- Lorenzo Rovigatti, Nicoletta Gnan, Alberto Parola, Emanuela Zaccarelli
- Abstract
We investigate binary mixtures of large colloids interacting through soft potentials with small, ideal depletants. We show that softness has a dramatic effect on the resulting colloid-colloid effective potential when the depletant-to-colloid size ratio q is small, with significant consequences on the colloidal phase behaviour. We provide an exact relationship that allows us to obtain the effective pair potential for any type of colloid-depletant interaction in the case of ideal depletants, without having to rely on complicated and expensive full-mixture simulations. We also show that soft repulsion among depletants further enhances the tendency of colloids to aggregate. Our theoretical and numerical results demonstrate that - in the limit of small q - soft mixtures cannot be mapped onto hard systems and hence soft depletion is not a mere extension of the widely used Asakura-Oosawa potential.
- Organisation(s)
- Computational and Soft Matter Physics
- External organisation(s)
- Sapienza University of Rome, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Università degli Studi dell'Insubria
- Journal
- Soft Matter
- Volume
- 11
- Pages
- 692-700
- No. of pages
- 9
- ISSN
- 1744-683X
- DOI
- https://doi.org/10.1039/c4sm02218a
- Publication date
- 01-2015
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103023 Polymer physics, 103018 Materials physics, 103029 Statistical physics
- Keywords
- ASJC Scopus subject areas
- Condensed Matter Physics, Chemistry(all)
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/how-soft-repulsion-enhances-the-depletion-mechanism(147fa0ce-2c49-4ec2-bd4d-37c014e32d47).html