Masunov Artëm E, Wait Elizabeth E, Vasu Subith S
South Ural State University , Lenin pr. 76 , Chelyabinsk 454080 , Russia.
National Research Nuclear University MEPhI , Kashirskoye shosse 31 , Moscow , 115409 , Russia.
J Phys Chem A. 2018 Aug 9;122(31):6355-6359. doi: 10.1021/acs.jpca.8b04501. Epub 2018 Jul 31.
We investigated the reaction rates of OH + CO → H + CO in supercritical CO environment with and without additional CO molecule included in reactive complex. Ab initio potential energy surfaces previously reported a lower activation barrier and hence a catalytic effect of additional CO molecule. Here we solve the steady-state unimolecular master equations based on the Rice-Ramsperger-Kassel-Marcus theory (RRKM) and compare the rates for the two mechanisms. We found that the alternative reaction mechanism becomes faster at high pressure and low temperature, when the concentration of prereactive complex with additional CO molecule becomes appreciable. Therefore, this catalytic effect may be important for the chemical processes in CO solvent but is unlikely to play a role during combustion.
我们研究了在超临界CO环境中，反应复合物中包含或不包含额外CO分子时，OH + CO → H + CO的反应速率。先前的从头算势能面报道了较低的活化能垒，因此额外的CO分子具有催化作用。在这里，我们基于赖斯-拉姆斯佩格-卡塞尔-马库斯理论（RRKM）求解稳态单分子主方程，并比较两种机制的反应速率。我们发现，当含有额外CO分子的预反应复合物浓度变得可观时，在高压和低温下，替代反应机制会变得更快。因此，这种催化作用对于CO溶剂中的化学过程可能很重要，但在燃烧过程中不太可能起作用。
