Reactions of gas-phase species with small molecules are being actively studied to understand the elementary steps and mechanistic details of related condensed-phase processes.Activation of the very inert N≡N triple b...Reactions of gas-phase species with small molecules are being actively studied to understand the elementary steps and mechanistic details of related condensed-phase processes.Activation of the very inert N≡N triple bond of dinitrogen molecule by isolated gas-phase species has attracted considerable interest in the past few decades.Apart from molecular adsorption and dissociative adsorption,interesting processes such as C-N coupling and degenerate ligand exchange were discovered.The present review focuses on the recent progress on adsorption,activation,and functionalization of N2 by gas-phase species(particularly metal cluster ions)using mass spectrometry,infrared photo-dissociation spectroscopy,anion photoelectron spectroscopy,and quantum chemical calculations including density functional theory and high-level ab initio calculations.Recent advances including characterization of adsorption products,dependence of clusters’reactivity on their sizes and structures,and mechanisms of N≡N weakening and splitting have been emphasized and prospects have been discussed.展开更多
Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this...Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.展开更多
The In-N clusters form in the dilute nitride InxGa1-xNy As1-yalloys after annealing.It is found that the formation of the In-N clusters not only raises the N levels lying above the conduction band minimum(CBM)of In Ga...The In-N clusters form in the dilute nitride InxGa1-xNy As1-yalloys after annealing.It is found that the formation of the In-N clusters not only raises the N levels lying above the conduction band minimum(CBM)of In GaA s,but also raises the N levels below the CBM of In GaA s,leading to the variation of the impurity-host interaction.The blueshift of the band gap energy is relative to the variation of the impurity-host interaction.In order to describe the blueshift of the band gap energy due to the formation of the In-N clusters,a model is developed.It is found that the model can describe the blueshift of the band gap energy well.In addition,it is found the blueshift of the band gap energy due to the atom interdiffusion at the interface can be larger than that due to the formation of the In-N clusters.展开更多
基金supported by the National Natural Science Foundation of China(No.21833011 and No.21973101)the Youth Innovation Promotion Association CAS(No.2020034)the K.C.Wong Education Foundation。
文摘Reactions of gas-phase species with small molecules are being actively studied to understand the elementary steps and mechanistic details of related condensed-phase processes.Activation of the very inert N≡N triple bond of dinitrogen molecule by isolated gas-phase species has attracted considerable interest in the past few decades.Apart from molecular adsorption and dissociative adsorption,interesting processes such as C-N coupling and degenerate ligand exchange were discovered.The present review focuses on the recent progress on adsorption,activation,and functionalization of N2 by gas-phase species(particularly metal cluster ions)using mass spectrometry,infrared photo-dissociation spectroscopy,anion photoelectron spectroscopy,and quantum chemical calculations including density functional theory and high-level ab initio calculations.Recent advances including characterization of adsorption products,dependence of clusters’reactivity on their sizes and structures,and mechanisms of N≡N weakening and splitting have been emphasized and prospects have been discussed.
基金supported by the National Natural Science Foundation of China(No.21773297,No.21973108,and No.21921004)supported by the National Natural Science Foundation of China(No.21805258)supported by the National Natural Science Foundation of China(No.21973107)。
文摘Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.
基金Supported by the National Natural Science Foundation of China under Grant No.61504094Tinjin Research Program of Application Foundation and Advanced Technology under No.15JCYBJC16300Tianjin City High School Science and Technology Fund Planning Project No.20120609
文摘The In-N clusters form in the dilute nitride InxGa1-xNy As1-yalloys after annealing.It is found that the formation of the In-N clusters not only raises the N levels lying above the conduction band minimum(CBM)of In GaA s,but also raises the N levels below the CBM of In GaA s,leading to the variation of the impurity-host interaction.The blueshift of the band gap energy is relative to the variation of the impurity-host interaction.In order to describe the blueshift of the band gap energy due to the formation of the In-N clusters,a model is developed.It is found that the model can describe the blueshift of the band gap energy well.In addition,it is found the blueshift of the band gap energy due to the atom interdiffusion at the interface can be larger than that due to the formation of the In-N clusters.
