Determination of Standard Enthalpies of Formation of Organic Peroxides Using Calibration Dependencies

• Published in: ChemistrySelect (Weinheim) 2024-09, Vol.9 (34), p.n/a
• Main Author: Poskrebyshev, Gregory A.
• Format: Article
• Language: English
• Subjects: Calibration dependence; CBS-QB3; DFT; Enthalpy of formation; G3B3; Peroxide
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202304994

In the present work, the calibration dependencies for the M062X (i=1),B3LYP (i=2), wB97XD (i=3), M08HX (i=4), MN15 (i=5), G3B3 (i=6) and CBS‐QB3 (i=7) and several other modeling approaches are determined using the calculated values of ΔraHo of atomization and literature based values of ΔraHo(X,TAB) of 14 reference peroxides. These calibration dependencies are used for the determination of ΔraHo(X,CORRP)i and ΔfHo(X,CORRP)i of other peroxides. The coordination of values of ΔfHo(X,CORRP)i (i=1–7) by the intersection of their 3σPi intervals is used for the determination of the most consistent values of ΔfHo(X,MEANP). These values of ΔfHo(X,MEANP) are used for the determination of BDE of peroxides. It's demonstrated that the calculated and literature values of BDE are in agreement. Among the considered modeling approaches, the lowest uncertainties (σPi) are determined for the G3B3 (3.1 kJ/mol), CBS‐QB3 (4.1 kJ/mol), and M062X/6‐311++G(d,p) (6.1 kJ/mol) approaches. The calibration dependencies for the values of ΔraHo(X)i of peroxides (P, i=1–16), their values of RMSEPXi, and σPXi are determined. The coordination of the corrected values of ΔfHo(X,CORRP)i±3σPXi, derived from ΔraHo(X,CORRP)i (i=1–7), results in consistent values of ΔfHo(X, MEANP), which agree with their literature values. An agreement between the reported and calculated values of peroxide BDE, derived using the values of ΔfHo(X, MEANP), is also observed.