Theoretical Investigation On The Reaction Of CO And N₂O Catalyzed By Zr₂O₄⁺ And La-activated Oligomerization Of Acetylene To Naphthalene In Gas Phase By Density Functional Theory

In recent years,more and more attention has been paid to the air pollution.The N₂O and CO,which are most significant air pollution resource,have deeply researched in the filed of experiment and theory.According to some investigations,transition metal oxide ions?MO⁺?as catalysts can effectively reduce the pollution of the N₂O and CO,because of their highly selectivity and activity.Therefore,the transition metal oxide ions?MO⁺?were applied as catalyst.Meanwhile,transition metal?M?and transition metal ions?M⁺?have peculiar activations to the C-H,C-O and C-C bonds of small organic compounds and reduce potential barrier to promote the reactions.To make better to explain these experimental facts,experimental chemists and theoretical chemists are discussing deeply the reaction mechanism.In this paper,the molecular orbital theory and transition state theory as the theoretical basis in quantum chemistry,the density functional theory?DFT?in its B3LYP formulation was applied.For this research system,we chosed the appropriate calculation method and basis set,the geometries of all species were fully optimized,and get the related experimental data,these date were used to analysis the reaction mechanism.The paper was divided into four chapters.The first chapter briefly introduced the development and application of quantum chemistry.The second chapter summarized the theory of quantum chemistry and calculation methods of this paper.The contents of the two chapters were the basis and background of our studies and offer us with useful and reliable quantum methods.The third chapter,To understand the remarkable catalytic property of Zr₂O₄⁺in the catalytic reaction of CO with N₂O,we emphatically analyzed and interprete the oxygen transfer process mechanism of CO oxidized Zr₂O₄⁺and N₂O reduced Zr₂O₃⁺in two step reactions on doublet potential energy surfaces.Finally,the turnover frequency?TOF?and X_TOF at 298K has been obtained by citing the energetic span model by Kozuch,which confirm excellent catalytic properties of Zr₂O₄⁺ion in the process of reaction.Chapter Four is the theoretical research on La-activated bicyclo-oligomerization of acetylene to form naphthalene.Recently,Dong-Sheng Yang and co-workers firstly reported that the reaction of the bare La atom mediated acetylene bicyclo-oligomerization formed naphthalene in the gas phase,and acetylene constant addition and dehydrogenation.In this reaction process,two possible reaction pathways were identified:?1?LaC₄H₂ is formed by a second addition of acetylene molecule to LaC₂H₂ followed by dehydrogenation?path?a??.?2?First,dehydrogenation of LaC₂H₂,followed by the addition of a second acetylene molecule?path?b??,we found that the optimum pathway was path?a?.For further analysis of the observed kinetic behavior,the energetic span model was utilized,and confirmed the determining transition state?TDTS?and determining intermediate?TDI?of the overall reaction.At the same time evaluated the properties of catalyst.The acetylene bicyclo-oligomerization reaction mediated by La atom always occurs along the doublet potential energy surface,which is the lowest energy path of the overall reaction.And maked the corresponding potential energy figure.