Random sequential adsorption of spheres on a cylinder

¹ Department of Physics, Harvard University - Cambridge, MA 02138, USA
² Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University Cambridge, MA 02138, USA
³ Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP - F-75005 Paris, France
⁴ Department of Organismic and Evolutionary Biology, Harvard University - Cambridge, MA 02138, USA
⁵ Kavli Institute for Nanobio Science and Technology, Harvard University - Cambridge, MA 02138, USA

^(b) lmahadev@g.harvard.edu (corresponding author)

Received: 2 May 2019
Accepted: 23 July 2019

Abstract

Inspired by observations of beads packed on a thin string in such systems as sea-grapes and dental plaque, we study the random sequential adsorption of spheres on a cylinder. We determine the asymptotic fractional coverage of the cylinder as a function of the sole parameter in the problem, the ratio of the sphere radius to the cylinder radius (for a very long cylinder) using a combination of analysis and numerical simulations. Examining the asymptotic structures, we find weak chiral ordering on sufficiently small spatial scales. Experiments involving colloidal microspheres that can attach irreversibly to a silica wire via electrostatic forces or DNA hybridization allow us to verify our predictions for the asymptotic coverage.