Theoretical study on the molecular structures and thermodynamic properties of polychlorinated pyrenes

Molecular geometric structures of 287 polychlorinated pyrenes (PCPYs) have been optimized with DFT-B3LYP/6-311G(d,p) method and their thermodynamic properties in the ideal gas state have been calculated, from which one can observe the relations of PCPYs's structures and thermodynamic properties with the number and position of chlorine atoms. The relative stability of PCPY isomers has been theoretically proposed on the basis of the magnitude of the relative standard Gibbs free energy of formation and compared with that of polychlorinated fluoranthene congeners.