| Comments |
"Molecules in solution have degrees of freedom of overall translation and rotation, as well as internal rotations about single bonds, that become highly constrained when two molecules associate to form a stable complex. [Investigators] have considered the thermodynamics of fusion and sublimation of hydrocarbons and polar organic molecules as instructive models for features of complex dissociation. The entropy of fusion within homologous series of alkanes, alkyl carboxylic acids, and 2-methyl ketones provides an estimate of the entropic cost of restricting a rotor, within a hydrocarbon chain, as -1.6 to -3.6 kJ/mol (T?S at 300 K) upon crystallization." |