Heat of Liquid Surface Formation and Evaporation

A simple analysis was proposed, which was based on purely spherical geometrical packing of molecules (most of which are certainly not spherical) and ideal situation. Hence, any deviation from 

Ratio of Enthalpy of Surface Formation, and the Enthalpies of Vaporization, hy3p (See Text for Details) 

Stefans law is an indication that the surface molecules are oriented differently than in the bulk phase. This observation is useful in order to understand the surface phenomena. 

As an example, one may proceed with this theory and estimate the surface tension of a liquid with data on its heat of evaporation. The number of near neighbors of a surface molecule will be about half (6=12 [near neighbors in the bulk phase]/2) than those in the bulk phase (12 neighbors). It is now possible to estimate the ratio of the attractive energies in the bulk and in the surface, per molecule. We have the following data for a liquid such as CCI4  

If we assume that about half of energy is gained when a molecule is transferred to the surface, then we get 

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