The Effect of Self-Poisoning on Crystal Morphology and Growth Rates

Recent extensive experimental work and the limited theoretical studies of the phenomenon ofself-poisoning of the crystal growth face are reviewed. The effect arises from incorrect but nearlystable stem attachments which obstruct productive growth. Experimental data on the temperature andconcentration dependence of growth rates and the morphology of long-chain monodisperse n-alkanesfrom C162H326 to C390H782are surveyed and compared to some previously established data on poly(ethylene oxide) fractions, aswell as on polyethylene. The anomalous growth rate minima in both temperature and concentration dependenceof growth rates are accompanied by profound changes in crystal habits, which have been analysed interms of growth rates on different crystallographic faces, and in terms of separate rates of stepnucleation and propagation. In some cases non-nucleated rough-surface growth is approached. Thephenomena covered include “poisoning” minima induced by guest species, the “dilutionwave” effect, autocatalytic crystallization, pre-ordering in solution, two-dimensional nucleation,and the kinetic roughening and tilt of basal surfaces.