Experimental methods based on gas-phase chromatography were tested with a view to determine the gas–liquid n-hexadecane partition coefficients, log L 16 of non-volatile compounds at 298.2 K. It was demonstrated that reliable values of log L 16 of compounds more volatile than n-docosane can be obtained using either capillary, or packed columns. The main limitation of both methods is the column stability at high temperatures. Here we propose a new method based on the temperature gradient mode, to obtain log L 16 of high-boiling compounds. A group contribution model is also presented in view to predicting log L 16 values of non-volatile compounds.