Bond Dissociation Energies and Electronic Structures in a Series of Peroxy Radicals: A Theoretical Study

作者：Zeng, Hui; Zhao, Jun^*

来源：Journal of the Chinese Chemical Society, 2014, 61(5): 556-562.

DOI：10.1002/jccs.201300455

• Bond dissociation energy
• Energy gap
• Substituent effect
• Quantum chemical method

Quantum chemical calculations are performed to estimate the bond dissociation energies (BDEs) for 18 peroxy radicals. Since DFT methods are researched to have low basis sets sensitivity, these radicals are studied by utilizing the hybrid density functional theory (DFT) (B3LYP, B3P86, B3PW91 and PBE1PBE) in conjunction with the 6-311G** basis set and the complete basis set (CBS-Q) method. On the basis of comparisons of the computational results and the experimental values, we evaluate the effectiveness of above methods. It is demonstrated that CBS-Q method is the best method for computing the reliable BDEs of COO bond, with the average absolute errors of 2.1 kcal/mol. So CBS-Q method is suitable to predict accurate BDEs of C-OO bond for peroxy compounds. The computational energy gaps between the HOMO and LUMO of studied compounds are almost identical from the point of view of stability and substantial HOMO-LUMO gaps for all molecules suggest their electronic stability. In addition, substituent effect on the COO BDE of peroxy radicals is analyzed. It is noted that the effects of substitution on the COO BDE of peroxy radicals are significant. Our results will shed lights on future theoretical and experimental work.

• 出版日期2014-5
• 单位长江大学