Determination of descriptors for polycyclic aromatic hydrocarbons and related compounds by chromatographic methods and liquid–liquid partition in totally organic biphasic systems

• Validation of descriptor quality.
• Atom fragment model for estimating descriptors.
• Prediction of water-based system properties.
• Nonaqueous systems to determine descriptors.

SummaryRetention factors on several columns and at various temperatures using gas chromatography and from reversed-phase liquid chromatography on a SunFire C18 column with various mobile phase compositions containing acetonitrile, methanol and tetrahydrofuran as strength adjusting solvents are combined with liquid–liquid partition coefficients in totally organic biphasic systems to calculate descriptors for 23 polycyclic aromatic hydrocarbons and eighteen related compounds of environmental interest. The use of a consistent protocol for the above measurements provides descriptors that are more self consistent for the estimation of physicochemical properties (octanol–water, air–octanol, air–water, aqueous solubility, and subcooled liquid vapor pressure). The descriptor in this report tend to have smaller values for the L and E descriptors and random differences in the B and S descriptors compared with literature sources. A simple atom fragment constant model is proposed for the estimation of descriptors from structure for polycyclic aromatic hydrocarbons. The new descriptors show no bias in the prediction of the air–water partition coefficient for polycyclic aromatic hydrocarbons unlike the literature values.