The geometric structure, mechanism of detonation initiation and stability of transition metal carbohydrazide （CHZ） nitrates are investigated via density functional theory. The obtained results show that the Heyd-Scu...The geometric structure, mechanism of detonation initiation and stability of transition metal carbohydrazide （CHZ） nitrates are investigated via density functional theory. The obtained results show that the Heyd-Scuseria-Ernzerhof （HSE） functional yields the most accurate geometry. The initiating reaction of detonation in [Mn（CHZ）3]（NO3）2 and [Zn（CHZ）3]（NO3）2 is the formation of NO3 radicals. The calculated heat of formation and energy gap predict that the Mn and Zn complexes, which have the half-filled （3d5） and full-filled （3d10） electron configurations for the transition metal ions, respectively are more stable than the Co, Ni and Cu complexes. This indicates that the electron configuration of transition metal ion plays an important role in the stabilities of these energetic complexes.展开更多
An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The stru...An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The structure exhibits two types of π-π stacking interactions between the nitroformate anions, i e, the parallel-displaced and T-shaped confgurafions. Furthermore, the thermal decomposition mechanism was investigated by DSC, TG-DTG and FTIR techniques. The kinetic parameters of the thermal decomposition were also calculated by using Kissinger＇s and Ozawa-Doyle＇s methods. The results show that NaNF has a good thermal stability, which is attributed to the π-π stacking interactions.展开更多
The microcosmic reaction mechanism of K2CO3-catalyzed 1-chlo-2-propanol and carbon dioxide has been investigated by density functional theory（DFT） at the GGA/PW91/DNP level.We optimize the geometric configurations o...The microcosmic reaction mechanism of K2CO3-catalyzed 1-chlo-2-propanol and carbon dioxide has been investigated by density functional theory（DFT） at the GGA/PW91/DNP level.We optimize the geometric configurations of reactants,intermediates,transition states,and products.The energy analysis calculation approves the authenticity of intermediates and transition states.According to our calculations,four feasible reaction pathways are found.The main pathway of the reaction is ReA → IMA1 → TSA1 → IMA2 → IMA5 → TSA5 → P.Besides,we also in-vestigate the reaction mechanism of 1-chlo-2-propanol and carbon dioxide without K2CO3-catalyzation by the same theory and level.The computational results indicate that the activation barrier with K2CO3-catalyzed is smaller than the activation barrier without K2CO3-catalyzed.That is to say,K2CO3 can promote the reaction to give the product in a high yield,which is in agreement with the experimental results.展开更多
The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-（2-methoxyphenyl）-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by densit...The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-（2-methoxyphenyl）-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.展开更多
基金National Natural Science Foundation of China(11272292,11372288)National High Technology Research and Development Program of China(863Program)(2013AA050905)+2 种基金the Chunhui Program of Ministry of Education of China(Z2014084)Development Foundation of CAEP(2014B0302041)Young Talent Foundation of Institute of Chemical Materials(KJZX-201403)
基金supported by the National Natural Science Foundation of China(No.20471008)the Natural Science Foundation of Chongqing(No.cstc2011jjA50013)the Chongqing Municipal Commission of Education(No.KJ111310)
文摘The geometric structure, mechanism of detonation initiation and stability of transition metal carbohydrazide （CHZ） nitrates are investigated via density functional theory. The obtained results show that the Heyd-Scuseria-Ernzerhof （HSE） functional yields the most accurate geometry. The initiating reaction of detonation in [Mn（CHZ）3]（NO3）2 and [Zn（CHZ）3]（NO3）2 is the formation of NO3 radicals. The calculated heat of formation and energy gap predict that the Mn and Zn complexes, which have the half-filled （3d5） and full-filled （3d10） electron configurations for the transition metal ions, respectively are more stable than the Co, Ni and Cu complexes. This indicates that the electron configuration of transition metal ion plays an important role in the stabilities of these energetic complexes.
基金Funded by the National"973"Projectthe National Natural Science Foundation of China(No.20471008)+1 种基金the Natural Science Foundation of Chongqing(No.cstc2011jjA50013)the Chongqing Municipal Commission of Education(No.KJ111310)
文摘An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The structure exhibits two types of π-π stacking interactions between the nitroformate anions, i e, the parallel-displaced and T-shaped confgurafions. Furthermore, the thermal decomposition mechanism was investigated by DSC, TG-DTG and FTIR techniques. The kinetic parameters of the thermal decomposition were also calculated by using Kissinger＇s and Ozawa-Doyle＇s methods. The results show that NaNF has a good thermal stability, which is attributed to the π-π stacking interactions.
基金Project supported by the Natural Science Foundation of Education Committee of Chongqing (No. KJ091311)
文摘The microcosmic reaction mechanism of K2CO3-catalyzed 1-chlo-2-propanol and carbon dioxide has been investigated by density functional theory（DFT） at the GGA/PW91/DNP level.We optimize the geometric configurations of reactants,intermediates,transition states,and products.The energy analysis calculation approves the authenticity of intermediates and transition states.According to our calculations,four feasible reaction pathways are found.The main pathway of the reaction is ReA → IMA1 → TSA1 → IMA2 → IMA5 → TSA5 → P.Besides,we also in-vestigate the reaction mechanism of 1-chlo-2-propanol and carbon dioxide without K2CO3-catalyzation by the same theory and level.The computational results indicate that the activation barrier with K2CO3-catalyzed is smaller than the activation barrier without K2CO3-catalyzed.That is to say,K2CO3 can promote the reaction to give the product in a high yield,which is in agreement with the experimental results.
基金Project supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1601215,KJ15012002)the Ministry of Education “Chunhui Plan”(Z2016177)
文摘The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-（2-methoxyphenyl）-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.
