(H2O)n(n=1-3)对HN(NO2)2→HONONNO2氢迁移反应的影响  

Effects of(H_2O)_n(n = 1—3) on hydrogen transfer process of HN(NO_2)_2→HONONNO_2

作　　者：张田雷[1] 贾子龙[1] 王炳楠[1] 

机构地区：[1]陕西理工大学化学与环境科学学院,陕西省催化基础与应用重点实验室,陕西汉中723000

出　　处：《陕西理工学院学报（自然科学版）》2016年第6期57-64,共8页Journal of Shananxi University of Technology:Natural Science Edition

基　　金：国家自然科学基金资助项目(21603132);陕西省教育厅科研计划项目(14JK1154)

摘　　要：采用CBS-QB3方法对HN(NO_2)2→HONONNO_2氢迁移机理和速率常数进行理论研究,并在此基础上考虑了水簇(H_2O)_n(n=1—3)对该反应机理及速率常数的影响。结果表明,HN(NO_2)_2→HONONNO_2氢迁移过程需克服33.8 kcal/mol的能垒。水簇(H_2O)_n(n=1—3)的加入不仅使得氢转移方式从原有反应中的直接抽氢转变为双、三、四氢原子协同转移,而且使得反应能垒降低了15.2~22.8 kcal/mol。其中,(H_2O)_3的参与使能垒降低22.8 kcal/mol,而(H_2O)_2和H_2O使其分别降低22.5 kcal/mol和15.2 kcal/mol。此外,在200~1 000 K温度范围内(H_2O)_3参与使通道的速率常数k3比相同温度下无水参与通道的速率常数k0大了4.2×10~3~6.9×10^(24)倍,说明在200~1 000 K温度范围内(H_2O)_3对HN(NO_2)_2→HONONNO_2氢迁移反应所起的正催化作用最大。The effect of （H2O）,（ n=1-3） on the hydrogen abstraction reaction of HN （ NO2 ） 2 HONONNO2 has been investigated by employing CBS-QB3 method and conventional transition state theory with wigner tunneling correction. The reaction without catalysts overcomes the barrier height of 33.8 kcal/mol to form HONONNO2. （H2O）,（ n=1-3） does not change the product of the reaction, but the direct hydrogen abstraction mechanism changes to double, three, and four hydrogen transfer mechanism. Compared with the naked reaction, the barrier height of the hydrogen abstraction reaction with （H2O）,（ n=1-3） is lower by 15.2 - 22.8 kcal/mol. Moreover, the barrier height of （H2O）3 assisted reaction is the lowest. Besides, the rate constants without and with catalyst show that the rate constant of （H=O）3-assisted channel is predicted to be faster by 4.2 × 10^3 - 6.9 × 10^24 times than that of the naked hydrogen transfer reaction at 200 - 1000 K, showing that, in temperature range 200 - 1000 K, the （HEO） 3 plays a positive catalytic role for the reaction of HN（ NO2）2→HONONNO2.

关 键 词：HN(NO2)2 H2O 氢迁移 反应机理 速率常数 

分 类 号：O643.1[理学—物理化学]