Procedure for estimating the heats of formation of aromatic compounds. Part II. Chlorinated phenols, biphenyls, diphenyl ethers and dibenzofurans

Abstract

A previously developed group contribution method is used to estimate the gas phase enthalpies (heats) of formation of chlorinated phenols, diphenyl ethers and dibenzofurans. A slight extension of the method is used to estimate the gas phase enthalpies (heats) of formation of chlorinated biphenyls. In general, it is noted that the enthalpy of formation tends to be lower with increased degree of chlorination and with increased oxygen content in the molecules. Variations among isomers are attributable to nearest neighbor effects when using the method described herein. Limitations of the method are briefly discussed.