The structuredness of solvents. 2. Data for ambient conditions

In view of the inadequacy of Trouton's constant for the expression of the structuredness of solvents at ambient temperatures, alternative measures have been sought. Calculations of the entropy deficit _vapS⁰/R of solvents at ambient conditions relative to their vapors and compared to presumably unstructured alkanes with the same number and arrangement of skeletal atoms have been made. Data for nonpolar, dipolar aprotic, non-hydroxylic protic and hydroxylic solvents are presented, with _vapS⁰/R>2 representing structured solvents. Empirically, the heat capacity density of solvents at ambient temperatures, C _p (l)-C _p (g)]/V], is another meaningful measure of the structuredness of solvents, compatible with the former one. Values>0.6 J-K^–1-cm^–3 signify a structured solvent.