Thermochemical properties and relative stability of polychlorinated biphenyls

The values of thermochemical quantities (enthalpy and Gibbs energy of formation, entropy and molar heat capacity) in the ideal gas state and dihedral angles for all 209 polychlorinated biphenyls were obtained by the Benson contribution method and ab initio calculations. The di-, tri- and tetra-ortho-chlorinated biphenyls are related with properties of WHO non-ortho- and mono-ortho-biphenyls in connection with their potential human toxicities.