Enthalpies of formation of molecular addition compounds in tetrachloromethane + p-xylene, + toluene, and + benzene from (solid + liquid) phase equilibria

Making Benzamide Cocrystals with Benzoic Acids: The Influence of Chemical Structure.

“…This failure was suggested to be due to the sensitivity of the force fields used to the pyramidalization of the benzamide amide group. However, the enthalpy of formation of a cocrystal may be determined experimentally from the heat of fusion of the cocrystal and starting components and consideration of the binary phase diagram . A number of multicomponent systems have shown to be entropically stabilized and have a positive enthalpy of formation .…”

“…However, the enthalpy of formation of a cocrystal may be determined experimentally from the heat of fusion of the cocrystal and starting components and consideration of the binary phase diagram. 41 A number of multicomponent systems have shown to be entropically stabilized and have a positive enthalpy of formation. 42 The binary phase diagram (Figure 11) for salicylic acid/benzamide indicates that the cocrystal has a lower melting point than either of the two starting materials.…”

Dielectric properties of liquid systems: study of interactions in the systems carbon tetrachloride with benzene, toluene, and p-xylene

“…It is interesting to note at this point that an inverse sequence was found by Rosseinsky and Kellawi [17] when they plotted the association constant for complexes of CCl 4 with benzene and methyl substituted benzene vs. number of CH 3 substituents. Evidence for the existence of electron-donor-acceptor interactions between CCl 4 and the aromatic molecules can be found in the literature through values of enthalpies of mixing or melting points [5,18,19]. In dielectric data they can only be…”

“…In previous work we studied the intermolecular associations in liquids through theoretical and experimental studies of the dielectric behavior of binary liquid mixtures [1][2][3][4]. In the present work on intermolecular associations in liquids we report measurements of permittivities, refractive indices, and densities for the CCl 4 þ C 6 H 6 , + C 6 H 5 CH 3 , and + p À ðCH 3 Þ 2 C 6 H 4 mixtures over the whole range of concentrations at 298.15 K. These mixtures are of considerable interest because in them the departures from ideality stems not only from dispersion, dipolar, and inductive forces, but also from the specific interactions that lead to the formation of chargetransfer complexes between the vacant 3D level of the chlorine atom in CCl 4 and the π cloud of the aromatic hydrocarbons [5,6]. In particular the studies of the static permittivity of solutions, measured with high precision, has the advantage that the experimental values are very sensitive to the existence of different interaction products that may be formed in the mixtures [7].…”