CRYSTAL NUCLEATION IN THE PRESENCE OF A METASTABLE CRITICAL-POINT

Density functional theory is applied to the study of crystal nucleatio n in the presence of a metastable critical point. A phenomenological m odel for fluids with short range interactions is developed to study th e influence of critical density fluctuations on the structure of the c ritical nucleus and the height of the barrier to nucleation. Our resul ts show dramatic changes in the nature of crystal nucleation near the metastable critical point, with nucleation rates increasing several or ders of magnitude; this behavior has important consequences for nuclea tion of colloids and proteins from solution. A nonmonotonic dependence of the critical cluster size on supersaturation is observed under the se conditions. (C) 1998 American Institute of Physics. [S0021-9606(98) 51325-6].