A second order group contribution method for the prediction of critical temperatures and enthalpies of vaporization of organic compounds

Extension of polar GC-SAFT to systems containing some oxygenated compounds: Application to ethers, aldehydes and ketones

“…In many of these methods, the influence of the group environment is neglected in first approximation (1st order GC methods) although it may be significant in some cases. Some authors (Constantinou and Gani [28], Georgeton and Teja [29], Dalmazzone et al [30], Tihic et al [31]) have tried to incorporate quite systematically this influence (2nd order GC methods) to improve the computation/prediction accuracy. In some other GC methods, such as GC-SAFT, the parameters values of certain groups may depend on their environment.…”

The New Method for Correlation and Prediction of Thermophysical Properties of Fluids. Critical Temperature

“…Group contribution (GC) method is the most widely used and studied by many scientists − because of its advantages of simple form and convenient calculation. It should be pointed out that the isomers have the same or almost the same groups, making the conventional GC method relatively backward in predicting research because it cannot distinguish isomers and ignores interactions between bonds.…”

“…It should be pointed out that the isomers have the same or almost the same groups, making the conventional GC method relatively backward in predicting research because it cannot distinguish isomers and ignores interactions between bonds. In order to overcome these defects, the secondary group was introduced , or the contributions of interactions between bonding groups in the molecule were considered, which resulted in significant improvement in accuracy. Xu et al , considered the specific position of a group in the molecule and developed a group vector space method for estimating the T c of organic compounds, which showed significant improvements in accuracy and applicability compared to the conventional GC methods.…”

Prediction of the enthalpy of vaporization based on modified Randič indices. Ethers

“…Results and discussion. In order to evaluate the prediction of the enthalpies of vaporization, the results obtained by the proposed methods and by other calculation approaches described in the literature [5][6][7][8][9] were compared ( Table 2).…”

“…At the same time, the additive method proposed by Domalski[6] and Dalmazzone's additive-correlation method[9] are less efficient in prediction, namely for the structures with a tert-butyl moiety. The former provides underestimated data, while the latter gives overestimated results.…”