4. Crystal growth

The growth of a condensed phase—whether liquid or solid—from its supersaturated parent phase is measured by the net flux of matter across the interface. However, in the overall transport mechanism, the incorporation of molecules into growth sites is not the only step that can impede this flux. Other steps, such as the attachment and accommodation of molecules from the immediate vicinity of the interface onto the interface itself, or diffusion within the parent phase, can slow growth just as much as interfacial kinetics. Since the applied supersaturation comprises the difference between the chemical potential of the parent phase, at an infinite distance from the surface, and that of the condensed phase, it is clear that each of the steps in question has as its driving force a fraction of the supersaturation, which does not facilitate the calculation of the growth rate of a crystal face, which...