Colloidal particles absorbed at the interface of a liquid droplet arrange into unique packings during slow evaporation (Manoharan et al. Science 301 pp 483-487). We present a numerical and theoretical analysis of the packing selection problem. The selection of a unique packing arises almost entirely from geometrical constraints during the drying.
@article{arxiv.cond-mat/0404236,
title = {Evaporation-driven assembly of colloidal particles},
author = {Eric Lauga and Michael P. Brenner},
journal= {arXiv preprint arXiv:cond-mat/0404236},
year = {2008}
}