Two models have been developed. Equation 1 is based on 78 experimental membrane/water partition coefficients measured at UFZ. Equation 2 additionally includes experimental data from literature, yielding a total training set of 197 chemicals. Both models are characterised by main contributions of the hydrogen bond acceptor strength and of the molecule size, with minor but still significant contributions of the excess molar refraction, polarity/polarisability, and hydrogen bond donor strength.
The models are ready for use. They are implemented in the software system ChemProp, together with their applicability domain in terms of the chemical space. A publication will be submitted soon.