화학공학소재연구정보센터
Journal of Chemical Physics, Vol.114, No.20, 9059-9068, 2001
Density functional theory of the kinetics of crystallization of a hard sphere suspension: Coupling structure to density
A theoretical study is presented on the kinetics of crystallization of a colloidal suspension in a fixed volume based upon the use of time dependent density functional theory incorporating conserved particle and nonconserved structure dynamics. This is a continuation of previous work done with conserved particle dynamics alone. The constraints of fixed number and volume lead to nonuniform solutions to the time independent equations of motion. One of the nonuniform solutions is found to have the minimum free energy and is identified as the stable equilibrium coexistence of crystalline and disordered suspension. Numerical integration is used to follow the time dependent motion of a range of initial crystallites. A broadband of stationary states, additional to those identified analytically, are located by the numerical integration. We show that these solutions arise from pinning induced by the discretization of space. The normal and tangential osmotic pressure fields are given and the growing crystallite is shown to be isolated from the higher pressure of the surrounding disordered suspension by the nonequilibrium depletion zone that surrounds it. These results are compared with recent light scattering studies.