Confinement effects on the configurational order of monodisperse disk packings

TL;DR

This study investigates how confinement influences the structural order and packing density distribution of monodisperse disks in confined geometries, revealing symmetry effects and size-dependent packing behaviors.

Contribution

It demonstrates the impact of confinement on the symmetry and packing fraction distribution of monodisperse disk packings, highlighting the role of finite size and surface effects.

Findings

Confinement determines the symmetry of packed configurations.

Probability density of packing fraction shows size-dependent peaks.

High-symmetry configurations occur due to monodispersity and confinement.

Abstract

Monodisperse circular disks have been collectively packed in confined geometries using a Monte Carlo method where the compaction is propelled by two- dimensional stochastic agitation. We have found that confinement (i.e., finite-size plus surface effects) determines the symmetry of the packed configurations together with the size evolution of the probability density of the packing fraction. For the particular case of small systems in square containers, the probability density of the packing fraction shows several well-defined peaks, depending on the system size, for both hard- wall and periodic boundary conditions. High-symmetry configurations (other than the n\timesn square arrays) with non-negligible occurrence probabilities are found as a direct consequence of monodispersity and confinement.