Chemistry Institute, University of Bialystok, Hurtowa 1 15-399 Bialystok, Poland.
J Phys Chem A. 2009 Feb 26;113(8):1564-73. doi: 10.1021/jp808874j. Epub 2009 Feb 4.
The kinetics of the 1,4-intramolecular hydrogen migration in the alkyl radicals reaction class has been studied using reaction class transition-state theory combined with the linear energy relationship (LER) and barrier height grouping (BHG) approach. The rate constants for the reference reaction of n-C(4)H(9) were obtained by canonical variational transition-state theory (CVT) with the small curvature tunnelling (SCT) correction in the temperature range 300-3000 K with potential-energy surface information computed at the CCSD(T)/cc-pVDZ//BH&HLYP/cc-pVDZ level of theory. Error analyses indicate that RC-TST/LER, where only reaction energy is needed, and RC-TST/BHG, where no other information is needed, can predict rate constants for any reaction in this reaction class with excellent accuracy. Specifically, for this reaction class the RC-TST/LER method has less than 65% systematic errors in the predicted rate constants, while the RC-TST/BHG method has less than 80% error when compared to explicit rate calculations.
已使用反应类过渡态理论结合线性能量关系（LER）和势垒高度分组（BHG）方法研究了烷基自由基反应类中 1,4-分子内氢键迁移的动力学。通过正则变分过渡态理论（CVT）与小曲率隧道（SCT）校正，在 300-3000 K 的温度范围内获得了 n-C（4）H（9）的参考反应的速率常数，势能面信息在 CCSD（T）/cc-pVDZ//BH&HLYP/cc-pVDZ 理论水平上计算。误差分析表明，仅需要反应能的 RC-TST/LER 和不需要其他信息的 RC-TST/BHG 可以非常准确地预测该反应类中任何反应的速率常数。具体来说，对于这个反应类，RC-TST/LER 方法预测的速率常数的系统误差小于 65%，而 RC-TST/BHG 方法与显式速率计算相比的误差小于 80%。
