A reassessment of the bond dissociation energies of peroxides. An ab initio study
A reassessment of the bond dissociation energies of peroxides. An ab initio study
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DOI：
10.1021/ja961838i
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发表时间：
1996-12-18
影响因子：
15
通讯作者：
Schlegel, HB
中科院分区：
文献类型：
--
作者：
Bach, RD;Ayala, PY;Schlegel, HB
O-O键的强度在各种化学过程中具有根本的重要性。传统上，34千卡/摩尔的值被认为是一般的O-O键离解能。目前的高水平从头计算表明，O-O的平均键能明显更高，约为45 kcal/mol，并且键能对成键环境敏感。在G2水平上的理论计算得到298 K时HOOH的弯曲解离焓为50千卡/mol， CH3OOH为45千卡/mol， CH3OOCH3为39千卡/mol， HC(O)OOH和CH3C(O)OOH为48千卡/mol。G2（MP2）的结果是相似的，并且，另外，给出键解离焓为38千卡/mol过氧化二乙酰，49千卡/mol三氟过氧乙酸，23千卡/mol过氧化异丙烯和22千卡/mol过氧亚硝酸。
The strength of the O-O bond is of fundamental importance in a variety of chemical processes. Traditionally, a value of 34 kcal/mol has been ascribed to a generic O-O bond dissociation energy. The present, high-level ab initio calculations indicate that the average O-O bond energy is significantly higher, ca. 45 kcal/mol, and that the bond energy is sensitive to the bonding environment. Calculations at the G2 level of theory give bend dissociation enthalpies at 298 K of 50 kcal/mol for HOOH, 45 kcal/mol for CH3OOH, 39 kcal/mol for CH3OOCH3, and 48 kcal/mol for HC(O)OOH and CH3C(O)OOH. The G2(MP2) results are similar and, additionally, give bond dissociation enthalpies of 38 kcal/mol for diacetyl peroxide, 49 kcal/mol for trifluoroperoxyacetic acid, 23 kcal/mol for isopropenyl hydroperoxide, and 22 kcal/mol for peroxynitrous acid.