Topological Modeling of the Setschenow Constant

A correlation for the estimation of the Setschenow constant by sodium chloride was proposed based on a training set of 71 organic compounds and was validated with a test set of 30 organic compounds. The new model was compared with the Ni−Yalkowsky model, and the calculated results show that the two models give comparable accuracy. Because the new model does not require any experimental physicochemical properties in the calculation, it is predictive, simple, and easy to apply. This work shows again that molecular connectivity indices are useful structural descriptors in the quantitative structure−property relationship studies.