Estimating entropies and enthalpies of fusion of organic compounds

Thermochemistry of phenols: buttress effects in sterically hindered phenols

“…where R = 8.31451 J · K −1 · mol −1 ; b and c are Antoine equation parameters; Z is the difference in compression factors of vapor and liquid ( Z ≈ 1 was calculated using the Haagenmacher equation (27) for phenols at the reference temperature); T = 298.15 K. The enthalpies of vaporization estimated by using equation (3) (5,6) we have shown that, within the boundaries of ±1.0 kJ · mol −1 , the values of enthalpies of fusion for the alkylphenols could be (28) is in disagreement with our result l cr H o m = (17.57 ± 0.21) kJ · mol −1 at T = 404.2 K. However the higher temperature of fusion of our specimen confirmed its higher purity.…”

A new simple approach to predict entropy of fusion of nitroaromatic compounds

“…Moreover, the total entropy of fusion can also be defined as the sum of transition and the entropy of fusion from the crystal to the isotropic liquid. Chickos et al [12][13][14] developed group additivity method for estimating total entropy of fusion. Jain et al [16] have shown that the group additivity method of Chickos et al [12][13][14] is cumbersome as it employs for a large number of group contribution values.…”

“…There are different approaches for estimating fus S at the melting point of some classes of organic compounds [1,[9][10][11][12][13][14][15]. On the basis of Walden's rule, fus S for aromatic compounds with little flexibility, such as diphenyl and cyclopentane, is constant with a value of 56.5 J/K [16].…”

Estimation of vapour pressure, solubility in water, Henry’s law function, and Log Kow as a function of temperature for prediction of the environmental fate of chemicals

“…By measuring some members of a congener group by DSC to obtain accurate heats of fusion values, the results can be expanded using multiple regression with molecular descriptors to other compounds in the congener group [19]. A QSAR method to estimate ∆Sf is to calculate it as sum of molecular increments [20]. The results are often equal between isomers, and therefore less accurate than from method above.…”