Heterogenous primary nucleation starting from a fluid phase

Heterogenous primary nucleation starting from a fluid phase 

We are especially interested with the case of nucleation starting from a sohd on another solid. 

Let us consider the system made up of a solid support, a solid nucleus, and a fluid phase. 

It is not possible to go on with the problem in a quantitative way without fixing geometry we traditionally discuss the nucleation of droplets in the shape of segments of a sphere on a plane support. We prefer a shape more representative of reality in the case of sohd. 

If i7 is the area of the support, interfacial energy in the system in which the cluster is not in contact with the support is 

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