Shape of a Nucleus Is Related to Kinetic Parameters

It is reasonable to assume that the shape of the nanonucleus is similar to that of a critical nucleus with the sizes of r, rn, and n, that is  

As m is given by Equation (4.14), m becomes less than unity (m bl) with the increase of Ag AT. In this case we change the critical nucleus from 3D to 2D. As m should be an integer, rn of the 2D nucleus is given by m = 1 as follows  

Frank and Tosi consider three types of diffusion within the melt, within the interface and within the crystals. 

the diffusion process with the highest AE should become the main rate determinant in the nucleation process. Diffusion within the crystals is not well known, but it is sometimes important, for example, nucleation in a multicomponent system [11], and the chain sliding diffusion of polymer chains, which mainly controls the formation of folded-chain crystals (FCCs) and extended-chain crystals (ECCs) [14,15]. 

CNT shows that the two competing factors controlling the nucleation process, AG and AE.both correspond to the thermodynamic driving force and kinetic activation barrier in nucleation, respectively. 

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