Air Force Research Laboratory, Space Vehicles Directorate, Kirtland AFB, NM 87117-5776, USA.
Phys Chem Chem Phys. 2013 Jul 21;15(27):11257-67. doi: 10.1039/c3cp50335f. Epub 2013 May 31.
The ion-molecule reactions Fe(+) + N2O → FeO(+) + N2 and FeO(+) + CO → Fe(+) + CO2, which catalyze the reaction CO + N2O → CO2 + N2, have been studied over the temperature range 120-700 K using a variable temperature selected ion flow tube apparatus. Values of the rate constants for the former two reactions were experimentally derived as k2 (10(-11) cm(3) s(-1)) = 2.0(±0.3) (T/300)(-1.5(±0.2)) + 6.3(±0.9) exp(-515(±77)/T) and k3 (10(-10) cm(3) s(-1)) = 3.1(±0.1) (T/300)(-0.9(±0.1)). Characterizing the energy parameters of the reactions by density functional theory at the B3LYP/TZVP level, the rate constants are modeled, accounting for the intermediate formation of complexes. The reactions are characterized by nonstatistical intrinsic dynamics and rotation-dependent competition between forward and backward fluxes. For Fe(+) + N2O, sextet-quartet switching of the potential energy surfaces is quantified. The rate constant for the clustering reaction FeO(+) + N2O + He → FeO(N2O)(+) + He was also measured, being k4 (10(-27) cm(6) s(-1)) = 1.1(±0.1) (T/300)(-2.5(±0.1)) in the low pressure limit, and analyzed in terms of unimolecular rate theory.
Fe(+) + N2O → FeO(+) + N2 和 FeO(+) + CO → Fe(+) + CO2 的离子-分子反应，催化了 CO + N2O → CO2 + N2 的反应，已在 120-700 K 的温度范围内使用可变温度选择离子流管装置进行了研究。前两个反应的速率常数是通过实验推导出来的，k2 (10(-11) cm(3) s(-1)) = 2.0(±0.3) (T/300)(-1.5(±0.2)) + 6.3(±0.9) exp(-515(±77)/T) 和 k3 (10(-10) cm(3) s(-1)) = 3.1(±0.1) (T/300)(-0.9(±0.1))。通过密度泛函理论在 B3LYP/TZVP 水平上对反应的能量参数进行特征化，通过建模考虑复合物的中间形成，模拟了速率常数。这些反应的特征是非统计性的固有动力学和前向和后向通量之间的旋转依赖性竞争。对于 Fe(+) + N2O，势能面的 sextet-quartet 转换被量化了。FeO(+) + N2O + He → FeO(N2O)(+) + He 的聚类反应的速率常数也被测量到，在低压极限下，k4 (10(-27) cm(6) s(-1)) = 1.1(±0.1) (T/300)(-2.5(±0.1))，并根据单分子速率理论进行了分析。
