A mechanistic growth model for inorganic crystals: Growth mechanism

Abstract

Inorganic crystals grown from solution find wide application. A mechanistic growth model based on the spiral growth mechanism that operates at low supersaturation on inorganic crystal surfaces is presented. The long‐range electrostatic interactions on inorganic crystal surfaces are captured by methods developed in our previous article (Dandekar and Doherty, AIChE J., in press). The interactions of kink site growth units with the solvent molecules partially determine the growth kinetics. Relevant experimental parameters are systematically accounted for in the expression for the kink incorporation rate along step edges on the crystal surfaces. The growth model accurately predicts the asymmetric growth spirals on the surface of calcite crystals. The effect of supersaturation and ionic activity ratio on the step velocities of the acute and obtuse spiral edges is also correctly captured. This model can be used to predict the shapes of solution grown inorganic crystals and to engineer the growth process to design inorganic solids with functionally desirable shapes. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3720–3731, 2014