Group Contribution Approaches for Soil-water Partitioning

1xv is the index for the heteroatom-containing molecule and (1Xv) p is the index for the corresponding, nonpolar (np) hydrocarbon equivalent. Bahnick and Doucette [20] demonstrate the calculation of these descriptors for 2-chloroacetani-lide. A ]xv accounts for nondispersive molecular interaction. Testing this model on a validation set of 40 structurally diverse compounds resulted in a standard deviation for the experimental versus estimated values of 0.37. The comparison of this value with the standard error of estimate (5 = 0.34) from the regression model suggests this model can be used confidently within the range of these structures. 

4 GROUP CONTRIBUTION APPROACHES FOR SOIL-WATER PARTITIONING 

Model of Okouehi and Saeguaa For hydrocarbons and halogenated hydrocarbons, the following model has been suggested [23]  

Evaluating their test set, Okouehi and Saegusa concluded that the contribution of the / index could be ignored. 

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