The kinetics of calcite crystallization on polymers containing -C = O, functional group was investigated by the constant composition method. The apparent order for the crystallization process was found to be 2.2 +/- 0.3 indicative of a surface diffusion controlled mechanism. The number of ions forming the critical nucleus was found to be 3-6. These values were confirmed by quantum mechanical calculations using the PM3 method of the MOPAC program package. The surface energy of the growing phase was found to be 30-32 mJm(-2) approximately. The formation of calcite Was initiated through the interaction of Ca2+ ions with the negative end of the -C = 0 bond as concluded from the quantum mechanical calculations. (C) 2003 Elsevier Science B.V. All rights reserved.