The Corrected Values of Δ_rH^o(C_aH_bO_d, a≤16) of Atomization of the Aromatic Compounds and Their Uncertainties Determined Using Several Quantum Mechanical Approaches

Abstract

The empirical linear scaling dependencies between the literature (Δ r H o (X n ,TAB)) and the calculated (Δ r H o ((X n ) i ,CALC)) values of atomization of 31 reference aromatic and related compounds (T = 298.15 K), as well as their standard errors ((SE 4 ) i ffi(σ 4 )i, Stand.Dev.), are determined for the different quantum mechanical (QM i ) approaches. These dependencies are compared and used for the determination of the values of Δ r H o ((X n ) i ,CORRE) � 3(SE 4 ) i of atomization reactions of considered not reference aromatic compounds, as well as for the determination of their values ofinterval), determined using the intersections of the 3(SE 4 ) i intervals, are consistent with all QM i 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 (SE YE ) � 3.8 kJ/ mol of the calculated values of Δ f H o ((X n ) i ,CORRE) MEAN . The effects of the number of OÀ 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.

Mechanism and Thermochemistry of Radical Driven Partial Chain Oxidation of p‐Benzylphenol

“…However, in most of the cases, the differences between these values are lying within uncertainty ranges, determined for the values of Δ f H o (Y, MEAN). The relatively high difference, observed in the case of H 2 O 2 , can be partially attributed to the presence of two OH groups, mentioned previously [14] . At the same time, the lower limits of values of Δ f H o (Y, MEAN) of CH 3 O 2 H, H 2 O 2 and HO 2 • , which, are slightly higher than the upper limits of their literature values, demonstrate that at least one of the values of Δ f H o (Y i , CORR) for these compounds is less accurate than it is expected.…”

“…The uncertainties, reported for the values of Δ f H o (Y i , CORR) in Table 4, correspond to 3SE i . The values of Δ f H o (Y, MEAN) (±3SE Y ), determined from the intersection of 3SE i intervals of Δ f H o (Y i , CORR) values, [14] as well as their literature values of Δ f H o (Y, TAB), are reported in the same Table 4. The values of Δ f H o (Y i , CORR), used for the determination of the upper and lower limits, are italicboldfaced .…”

“…The methods and approaches, used in the present work, are the same those reported in [5,6,14] . The geometries of the considered reference ((X n ) i , reported in SI, Notes 3, Table S4 ) and studied (Y i ) compounds were optimized using the M06‐2X/6‐311++G(d,p) ( i =1), [23] B3LYP/6‐311++G(d,p) ( i =2), [24] wB97XD/6‐311++G(d,p) ( i =3), [25] M08HX/6‐311++G(d,p) ( i =4) [26] and MN15/6‐311++G(d,p) ( i =5) [27] DFT approaches.…”

“…In the case of atomization reactions, the values of Δ ra H o (Y i , CORR) were derived from the values of Δ ra H o (Y i ), determined using the values of H o of the gaseous C i , H i , O i and Y i , according to Hess's law. These values of Δ ra H o (Y i ) were corrected to the values of Δ ra H o (Y i , CORR) using the calibration dependencies (=(A 1 ) i +(B 1 ) i ×Δ ra H o (Y i )), coefficients (A 1 ) i and (B 1 ) i of which ( SI, Notes 2, Table S2 ), were determined previously for the set of 31 reference compounds (where X n =C a H b O d , a ≤ 16, n =1–31) [14] . The considered reference compounds and their literature values of Δ f H o (X n , TAB), presented in SI, Notes 3, Table S4 , were also used for the calculations of thermochemistry of homodesmotic reactions.…”

Theoretical study on the solvent‐free self‐catalyzed coupling mechanism of a chiral vicinal diamine and isobutyraldehyde mediated by the outgrowth H2O

“…All results presented in this work were calculated with Gaussian 09 package [34] by the M06‐2X method with double Hartree‐Fock exchange functionals [35–38] in conjunction with the standard 6–311+G(d) basis set [39–41] in gas phase. Geometries were fully relaxed, and frequency analysis was carried out to judge a local minimum without imaginary frequency or a transition state with only one imaginary frequency.…”