SummaryPart of this work focuses on temperature programmed retention index assessment of 70 polynuclear aromatic hydrocarbons (PAHs) using a methylsilicone capillary column. The use of the retention index presented here offers a good possibility of identifying and determining PAHs in the mass range discussed and to apply such conditions to the analysis of fuel and fuel deposits. Retention indices and vaporization enthalpy data of PAHs are linearly related to the molecular total energy. This paper describes also a gas-chromatographic study of the adsorption of some PAHs on Carbopack.