The two channels of the CH3OH+Cl hydrogen abstraction reaction, leading to the final products CH2OH+HCl (i) and CH3O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-valence ...The two channels of the CH3OH+Cl hydrogen abstraction reaction, leading to the final products CH2OH+HCl (i) and CH3O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-valence polarization basis sets. For each of the two channels the following simple reaction path is predicted: reactants → transition state → intermediate → products. The previously reported complicated paths2 calculated without using the IRC technique are criticized. Our calculations indicate that channel (i) is exothermic and has a negligible energy barrier while channel (ii) is endothermic and has a substantial energy barrier. These results imply that channel (i) is favorable, which is in line with experiment.展开更多
We propose the complicated catalytic mechanisms for the acetic acid molecule catalyzed by transition metal oxide MoO2 based on density functional theory calculations.The geometries and energetic values of all stationa...We propose the complicated catalytic mechanisms for the acetic acid molecule catalyzed by transition metal oxide MoO2 based on density functional theory calculations.The geometries and energetic values of all stationaries and transition states involved in the three different reaction pathways(ChannelsⅠ,ⅡandⅢ)are reported and analyzed.All reaction mechanisms are fully different from that of MoxOy catalyzing volatile organic compounds(VOCs)in previous studies.The completely new mechanisms catalyzed by MoO2 for acetic acid have been discovered for the first time.ChannelsⅠ(ⅠA andⅠB)andⅡare both addition reactions and channelⅢis hydrogen abstraction reaction by producing a leaving group.The barrier energies of reaction are also compared with other catalytic reactions,showing that MoO2 catalyst expresses a lower barrier energy(8.22 kcal/mol)by addition reaction,which represents MoO2 tends to absorb acetic acid pollution gas via addition reaction rather than release toxic substances.This also means that MoO2 is a more effective and representative catalyst and is suitable for further study of catalytic carboxylic acids,so the reaction mechanisms may provide a useful theoretical guidance and solution for the catalysis of carboxylic acids.展开更多
文摘The two channels of the CH3OH+Cl hydrogen abstraction reaction, leading to the final products CH2OH+HCl (i) and CH3O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-valence polarization basis sets. For each of the two channels the following simple reaction path is predicted: reactants → transition state → intermediate → products. The previously reported complicated paths2 calculated without using the IRC technique are criticized. Our calculations indicate that channel (i) is exothermic and has a negligible energy barrier while channel (ii) is endothermic and has a substantial energy barrier. These results imply that channel (i) is favorable, which is in line with experiment.
基金Supported by the Shanxi Provincial Education Department(2019L0986)the 2016 annual major science and technology projects of Shanxi Province(MC2016-02/5)+4 种基金the Shanxi Advantageous and Characteristic Disciplines of“Project 1331”the school fund of Shanxi Institute of Technology(201605000120180010012 and 20190040013)the major project of Tangshan Normal College(Nos.2017B01 and B02)the 2019 abroad training project fund of Tangshan excellent young and middle-aged experts。
文摘We propose the complicated catalytic mechanisms for the acetic acid molecule catalyzed by transition metal oxide MoO2 based on density functional theory calculations.The geometries and energetic values of all stationaries and transition states involved in the three different reaction pathways(ChannelsⅠ,ⅡandⅢ)are reported and analyzed.All reaction mechanisms are fully different from that of MoxOy catalyzing volatile organic compounds(VOCs)in previous studies.The completely new mechanisms catalyzed by MoO2 for acetic acid have been discovered for the first time.ChannelsⅠ(ⅠA andⅠB)andⅡare both addition reactions and channelⅢis hydrogen abstraction reaction by producing a leaving group.The barrier energies of reaction are also compared with other catalytic reactions,showing that MoO2 catalyst expresses a lower barrier energy(8.22 kcal/mol)by addition reaction,which represents MoO2 tends to absorb acetic acid pollution gas via addition reaction rather than release toxic substances.This also means that MoO2 is a more effective and representative catalyst and is suitable for further study of catalytic carboxylic acids,so the reaction mechanisms may provide a useful theoretical guidance and solution for the catalysis of carboxylic acids.