The empirical linear scaling dependencies between the literature (rHo(Xn,TAB)) and the calculated (rHo((Xn)i,CALC)) values of atomization of 31 reference aromatic and related compounds (T=298.15K), as well as their standard errors ((SE4)i(4)i, Stand.Dev.), are determined for the different quantum mechanical (QMi) approaches. These dependencies are compared and used for the determination of the values of rHo((Xn)i,CORRE)±3(SE4)i of atomization reactions of considered not reference aromatic compounds, as well as for the determination of their values of fHo((Xn)i,CORRE)±3(SE4)i. The values of fHo((Xn)i,CORRE)MEAN±3SEYE (≥99.4% confidence interval), determined using the intersections of the 3(SE4)i intervals, are consistent with all QMi approaches and their literature values. The M06-2X/6-311++G(d,p), M08HX/6-311++G(d,p) and wB97XD/6-311++G(d,p) approaches are recommended for the achievement of accuracy (SEYE)≤3.8 kJ/mol of the calculated values of fHo((Xn)i,CORRE)MEAN. The effects of the number of O-H groups, size and multiplicity of compounds on values of error, also studied in this work, demonstrate the limitations of using of several scaled dependencies.

In the present work, the standard thermochemical properties of the most thermochemically stable radicals (p-Benzylenephenol and 1-Methyl-2-methylene phthalate), formed by abstraction of the hydrogen atom from the p-Benzylphenol and Dimethyl phthalate are determined using the results of B3LYP/6-311++G(d,p), M06-2X/6-311++G(d,p) and RO/CBS-4M calculations. The consistent values of the standard enthalpies of formation of these structures are determined using the corrected thermochemistry of the homodesmotic and atomization reactions. The values of the standard entropies of these compounds and the temperature dependencies of their thermochemical properties are also calculated in the present work. It is found that the H-transfer reaction of HO2 with p-Benzylenephenol is thermochemically favorable and can lead to the chain oxidation of p-Benzylenephenol at relatively low temperatures.