Solubility parameter concept volume effects

The effect of mere difference between molecules, such as different size, shape, or polarizability, as it affects intermolecular forces was considered by Hildebrand and Scott (1962). They were led to the concepts of cohesive energy density (which is defined as the molar energy of evaporation divided by the molar volume, and which has the dimensions of pressure) and its square root, the solubility parameter, defined by ... 

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