Minimum Energy Conditions and Simple Theory of Growth

2 Minimum Energy Conditions and Simple Theory of Growth  

The dimensions of the crystal will be determined by the relative energy of each surface and will be a minimum with respect to the melt (AG) at a given volume  

Taking the derivatives of AG with respect to Li and L3 and setting each component equal to zero, the following expressions are obtained  

The Thompson-Gibbs (TG) equation (4-6) allows the melting point to be related to the lamella thickness. The change in free energy on melting (AG j) is given by 

For a simple pol3mier crystal, the lamellae dominate the growth and the two surfaces that contain the folded chains dominate the total surface energy term. It can be assumed that there is a free energy term that is independent of this fold surface and represents the interaction between the al -trans linear chains, stems, and has the form 

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