Molecular orientation entropy, solid surface

For liquids and solids, specific orientation and conformation of msymmetrical molecules (ions) in the interfacial regions result not only in the maximization of their interaction energy, but also yield entropy effects that cannot be neglected. For example, molecular dynamics calculations of the intermolecular potential function points to a predominant orientation of the water dipoles at the Liquid-Gas interface [45]. Other examples are an icelike structuring of water molecules in the vicinity of crystalline solid surfaces [46] and a specific orientation of the alcohol molecules in the interface between a liquid n-alkanol and water [47]. 

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