Effect of Impurities on the Growth Kinetics of Crystals

This paper reviews the work made by the group of the present author on the effect of impurities on the kinetics of crystal growth in solutions. The impurity effect is here discussed in the light of the model proposed by Kubota and Mullin [J. Crystal Growth, 152 (1995) 86], in which impurities are assumed to be adsorbed on the step lines at kink sites following the Langmuir mechanisms for inhibition of step displacement with a modified pinning mechanism. Effects of impurity concentration and supersaturation on impurity action on crystal growth are discussed successfully for various crystallizing systems with different impurities. Temperature effect on the impurity action is also discussed. Non-steady as well as steady state crystal growth behavior in the presence of impurities is discussed. Growth rate hysteresis in the presence of impurities and the pH effect on the impurity action of trivalent metallic impurities are discussed as well.