The kinetics of calcium carbonate hexahydrate crystallization on polymer containing -Cequivalent toN, functional group was investigated by he constant composition method. The presence of the above-mentioned functional group stabilize this calcium carbonate polymorph at room temperature which transforms slowly to vaterite. The apparent order for the crystallization process was found to be 4+/-0.3 indicative of a surface nucleation mechanism. The number of ions forming the critical nucleus was found to be p = 5. This value was confirmed by quantum mechanical calculations. The surface energy of the growing phase was 33 mJ m(-2). The formation of hexahydrate initiated through the interaction of Ca2+ ions with the negative end of the -Cequivalent toN bond. (C) 2002 Elsevier Science B.V. All rights reserved.