Group contribution approaches

Estimation methods for the surface tension of a liquid are based on eq. 5.1.1. Generally, pvap pi and pvap can be ignored. Thus one obtains 

Estimation of a with 5.3.1 requires solely the input of pi and parachor. Parachor can be derived from molecular structure with schemes based on group additivity. Exner [4] gives an excellent review and discussion of various group contribution methods for parachor. A very simple method has been developed by McGowan [5] employing only atomic contribution and the number of bonds, A bonds  

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Klopman G, S Wang and D M Balthasar 1992. Estimation of Aqueous Solubility of Organic Molecule by the Group Contribution Approach. Application to the Study of Biodegradation. Journal c Chemical Information and Computer Science 32 474-482. 

There are a number of reliable estimating techniques for obtaining pure-component hq uid heat capacity as a function of tem )erature, including Ruzicka and Dolmalsld, Tarakad and Danner, " and Lee and Kesler. These methods are somewhat compheated. The relatively single atomic group contribution approach of Chueh and Swanson for liquid heat capacity at 29.3.15 K is presented here ... 

Constantinou, L., Jacksland, C., Bagherpour, K., Gani R., and Bogle, L. (1995). Application of group contribution approach to tackle environmentally-related problems. AlChE Symp. Sen, 90(303) 105-116. 

Platts, J. A., Abraham, M. H., Butina, D., Hersey, A. Estimation of molecular linear free energy relationship descriptors by group contribution approach. 2. Prediction of partition coefficient. J. Chem. Inf. Comput. Sci. 2000, 40, 71-80. 

Klopman, G., U,). W., Wang, S., Dimayuga, M. Computer automated log P calculations based on an extended group contribution approach. 

D. M., Estimation of aqueous solubility of organic molecules by the group contribution approach. Application... 

Much effort has been expended on models that can be used to predict the solubility behavior of solutes, with good success being attained using a semi-empirical, group contribution approach [75]. In this system, the contributions made by individual functional groups are summed to yield a composite for the molecule, which implies a summation of free energy contributions from constituents. This method has proven to be useful in the prediction of solubility in water and in water-cosolvent mixtures. In addition to the simplest methodology, a variety of more sophisticated approaches to the prediction of compound solubility have been advanced [68]. 

Gani, R., Nielsen, B., Fredenslund, Aa., 1991, A Group Contribution Approach to Computer-Aided Molecular Design, AIChE Journal, 37 (9), 1318-1332. 

Estimations of the value of % can be obtained via the theory of the solubility parameter [17], or the group contribution approach [18],... 

For alkanes, the logarithm of viscosity has been correlated with atomic and with bond contributions to estimate tj at 0 and 20°C [13]. Considering a broader range of structural variety, neither the viscosity nor its logarithm is a constitutionally additive property. Application of the group contribution approach is based on additive parameters that allow viscosity estimations in combination with other experimental data such as density or vapor pressure. The viscosity-constitutional constant, /vc, is such an additive parameter ... 

UNIFAC Approach Jensen et al. [16] have employed the UNIFAC group contribution approach to develop an estimation method for pure-component vapor pressures. The model developed applies to hydrocarbons, alcohols, ketones, acids, and chloroalkanes of less than 500 molecular mass and in the vapor pressure region between 10 and 2000 mmHg. Burkhard et al. [8] extended this model to chlorinated aromatic compounds such as chlorobenzenes and PCBs. 

The group contribution approach has been employed in different ways to model the relation between Tb and molecular structure ... 

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