CRYSTALLIZATION IN SEDIMENTATION PROFILES OF HARD-SPHERES

Equilibrium density profiles of a hard-sphere suspension in a gravitat ional field are calculated using Monte Carlo simulations. For increasi ng gravity there is a discontinuous freezing transition induced by the container wall where few crystalline layers are spontaneously formed at the bottom of the sample. This crystalline part then grows continuo usly as the gravitational field is further enhanced. The results are c ompared with density functional theory of freezing where a weighted de nsity approximation is used. While good overall agreement of the later ally averaged profile and the lateral crystallinity is achieved, densi ty functional theory yields a discontinuous crystal growth via layerin g transitions.