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Reaction Mechanism and Kinetics for HCCO Radical with NO

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Chemical Research in Chinese Universities 2005年第1期21卷 92-95页

作者： LIUPeng-jun PANXiu-mei CHANGYing-fei SUZhong-min WANGRong-shun InstituteofFunctionalMaterialChemistry FacultyofChemistryNortheastNormalUniversityChangchun130024P.R.China／／ChemistryDepartmentofHainanNormalUniversityHaikou571158P.R.China InstituteofFunctionalMaterialChemistry FacultyofChemistryNortheastNormalUniversityChangchun130024P.R.China

The mechanism and dynamical properties for the reaction of HCCO radicals with NO were investigated theoretically. The minimum energy paths(MEP) of the reaction were calculated by using the density functional theory(DFT) at the B3LYP/6-311+G ** level, and the energies along the MEP were further refined at the QCISD(T)/6-311+G ** level. It is found that the reaction mechanism of the title reaction involves three channels, producing HCNO+CO, HONC+CO and HCN+CO 2 products, respectively. Channel 1 is the most favorable path. The rate constant for channel 1 were calculated over a temperature range of 800—2500 K by using the canonical variational transition-state theory(CVT). The rate constant for the main path is negatively dependent on temperature, which is a characteristic of radical reactions with negative activation energy, and the variational effect for the rate constant calculation is small in the whole temperature range.

关键词： Ketenyl radical(HCCO) NO Reaction mechanism Density functional theory(DFT) variational transition state

Theoretical Investigation on the Abstraction Reaction of H with (CH_3)_3SiH

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Chemical Research in Chinese Universities 2002年第1期18卷 47-51页

作者： ZHANG Qing-zhu WANG Ming-gang WANG Shao-kun ZHANG Miao LIU Chuan-pu GU Yue-shu Department of Chemistry Shandong UniversityJinan 250100P.R.China

The abstraction reaction of H with (CH_3)_3SiH was investigated at the high levels of ab initio molecule orbital theory. The geometries were optimized at the MP2 level with 6-31G( d ) basis set, and G2MP2 level was used for the final energy calculations. The theoretical analysis provides the conclusive evidence that the main process is the hydrogen abstraction from the Si-H bond, leading to the formation of H_2 and silyl radicals; the hydrogen abstraction from the C-H bond has a higher barrier and is difficult to react. The kinetics was calculated with canonical variational transition-state theory (CVT) over the temperature range 200-1 000 K, and the theoretical rate constants match well with the later experimental values.

关键词： Reaction mechanism variational transition state Tunneling effect Rate constant

Ab initio Calculation and Kinetic Study for the Abstraction Reaction of H with SiHCl_3

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Chinese Journal of Chemistry 2002年第3期20卷 214-219页

作者：张庆竹王少坤顾月姝 School of Chemistry and Chemical Engineering Shandong University Jinan Shandong 250100 China

The mechanism of the reaction of H with SiHCl_3 has been investigated at highlevel of ab initio molecular orbital theory. Theoretical analysis provides a conclusive evidencethat the main process occurring in this reaction is the hydrogen abstraction from the Si―H bond,the abstraction of Cl has higher barrier and is difficult to react. The kinetics has been studiedusing canonical variational transition-state theory (CVT) with small curvature tunneling effect(SCT) correction. The rate constants have been calculated over a wide temperature range of 200―3000K. The CVT/SCT rate constants exhibit typical non-Arrhenius behavior, a three-parameterrate-temperature formula is fitted as follows; k( T) = (3.24 x 10^(-19)) T^(2.30) exp( - 250/T) [inunit of mL/(molecule·s). The calculated CVT/SCT rate constants match well with the experimentalvalues.

关键词： trichlorosilane abstraction reaction variational transition state

Theoretical Investigation for the Abstraction Reaction of H with (CH_3)_3GeH

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Chinese Chemical Letters 2002年第12期13卷 1227-1230页

作者： Qing Zhu ZHANG Chun Sheng WANG Yue Shu GU School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100

ion reaction of H atom with (CH3)3GeH has been studied using ab initio molecular orbital theory. The kinetics calculation has been deduced using the canonical variational transition state theory (CVT) with the small-curvature tunneling correction method (SCT) over the temperature range of 200-3000 K. The CVT/SCT rate constants exhibit typical non-Arrhenius behavior, and a three-parameter rate-temperature formula has been fitted as follows: k=6.66×10-18T2.33 exp(-60.3/T) (in units of cm3 molecule-1 s-1).

关键词： Trimethylgermane ab initio calculation variational transition state rate constants.

Theoretical Studies on CH_3SiH_3+H→CH_3SiH_2+H_2 Reaction with the variational transitional state Theory

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Chinese Chemical Letters 2000年第2期11卷 119-122页

作者： Qing Zhu ZHANG Chuan Pu LIU Shao Kun WANG Xin Ji XIE Miao ZHANG Yue She GU (School of Chemistry. state Key Laboratory of Crystal Materials, Shandong University Jinan 250100) Shandong Univ Sch Chem State Key Lab Crystal Mat Jinan 250100 Peoples R China

In this paper. the abstraction reaction of CH_3SiH_3 with H has been studied by using the 'direct dynamics' method of variational transition-state theory. which is based on the information on geometries. frequencies and energies calculalcd by ab inito along the minimum energy path. The rate constants of the title reaction were calculated for the range of temperature 298-1700 K. The rate constants calculated match well with the experimental values.

关键词： variational transition state tunneling effect rate constants.

Theoretical Studies on the Abstraction Reaction of Atomic O(^3p) with Si2H6

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Chinese Chemical Letters 2002年第7期13卷 662-665页

作者： Qing Zhu ZHANG Chun Sheng WANG Shao Kun WANG Yue Shu GU School of Chemistry and chemical engineering Shandong UniversityJinan 250100

ion reaction of O (3P) with Si2H6 has been studied theoretically. Two transition states of 3A and 3A symmetries have been located for this abstraction reaction. Geometries have been optimized at the UMP2 level with 6-311G+(d) basis set. G3MP2 has been used for the final single-point energy calculation. The rate constants have been calculated over a wide temperature range of 200~3000 K using canonical variational transition-state theory (CVT) with small curvature tunneling effect (SCT). The calculated CVT/SCT rate constants match well with the experimental value.

关键词： O (3P) disilane ab initio calculation variational transition state rate constants.