In order to elucidate the unusual chemical sensitivity of binary indium bromides. thepotential energy surface of the model complex InBr87- has been studied by means of ah initio all-electron calculation with larger ba...In order to elucidate the unusual chemical sensitivity of binary indium bromides. thepotential energy surface of the model complex InBr87- has been studied by means of ah initio all-electron calculation with larger basis sets. The configuration is on a local maximum of the energysurface and crystal potential around In+ is soft, allowing small spontaneous distortions as a result ofa second-order Jahn-Teller instability.展开更多
The isomerization of singlet, nitryl hydride(HNO2) has beed studied by using abinitio method at MP2 level with 6-31G* basis set. The calculation indicates that the reaction isexothermic by 10.8kJ.mol-1, the energy bar...The isomerization of singlet, nitryl hydride(HNO2) has beed studied by using abinitio method at MP2 level with 6-31G* basis set. The calculation indicates that the reaction isexothermic by 10.8kJ.mol-1, the energy barrier is 227.9kJ·mol-1, and nitryl hydride is not easilyisomerized to trans-HONO.展开更多
Ah initio calculations have been performed for 6-X-2(1H)-Pyridones (X=H, NH2, Cl,CH3, NO2) and their tautomers in the gas phase and in aqueous solution at HF/6-311G level, the solvent effects were investigated with On...Ah initio calculations have been performed for 6-X-2(1H)-Pyridones (X=H, NH2, Cl,CH3, NO2) and their tautomers in the gas phase and in aqueous solution at HF/6-311G level, the solvent effects were investigated with Onsager SCRF model. The substituent effects predicted by theoretical calculations are in satisfactory agreement with the experimental values, and the results obtained indicate the significance of solvent effects involved in this system.展开更多
本文用 INDO 法研究了硫二氮杂环烷1.1—二氧化物模型分子（O<sub>2</sub>SN<sub>2</sub>H<sub>2</sub>）的几何结构、电子结构和化学链。结果不明,尽管某些参数与实验值和 ab initio 结果有较大...本文用 INDO 法研究了硫二氮杂环烷1.1—二氧化物模型分子（O<sub>2</sub>SN<sub>2</sub>H<sub>2</sub>）的几何结构、电子结构和化学链。结果不明,尽管某些参数与实验值和 ab initio 结果有较大的差异,但得到的分子构型为 OSO 平面垂直于 SNN 环平面及该分子主要通过2b1、3b1轨道成链的结果。在半经验近似条件下仍有参考价值。展开更多
Ab initio SCF and Moller-Plesset correlation correction methods incombination with counterpoise procedure for BSSE correction have been applied to the theroeticalstudying of dimethylnitroamine and its dimers and trime...Ab initio SCF and Moller-Plesset correlation correction methods incombination with counterpoise procedure for BSSE correction have been applied to the theroeticalstudying of dimethylnitroamine and its dimers and trimers. Three optimized stable dimers and twotrimers have been obtained. The corrected binding energies of the most stable dimer and trimer werepredicted to be - 24.68 kJ/mol and - 47.27 kJ/mol, respectively at the MP2/6-31G ~*//HF/6-31G~*level. The proportion of correlated interaction energies to their total interaction energies for allclusters was at least 29.3 percent, and the BSSE of ΔE(MP2) was at least 10.0 kJ/mol. Dispersionand/ or electrostatic force were dominant in all clusters. There exist cooperative effects in boththe chain and the cyclic trimers. The vibrational frequencies associated with N―O stretches or wagsexhibit slight red shifts, but the modes associated with the motion of hydrogen atoms of the methylgroup show somewhat blue shifts with respect to those of monomer. Thermodynamic properties ofdimethylnitroamine and its clusters at different temperatures have been calculated on the basis ofvibrational analyses. The changes of the Gibbs free energies for the aggregation from monomer to themost stable dimer and trimer were predicted to be 14.37 kJ/mol and 30.40 kJ/mol, respectively, at 1atm and 298.15 K.展开更多
文摘In order to elucidate the unusual chemical sensitivity of binary indium bromides. thepotential energy surface of the model complex InBr87- has been studied by means of ah initio all-electron calculation with larger basis sets. The configuration is on a local maximum of the energysurface and crystal potential around In+ is soft, allowing small spontaneous distortions as a result ofa second-order Jahn-Teller instability.
文摘The isomerization of singlet, nitryl hydride(HNO2) has beed studied by using abinitio method at MP2 level with 6-31G* basis set. The calculation indicates that the reaction isexothermic by 10.8kJ.mol-1, the energy barrier is 227.9kJ·mol-1, and nitryl hydride is not easilyisomerized to trans-HONO.
文摘Ah initio calculations have been performed for 6-X-2(1H)-Pyridones (X=H, NH2, Cl,CH3, NO2) and their tautomers in the gas phase and in aqueous solution at HF/6-311G level, the solvent effects were investigated with Onsager SCRF model. The substituent effects predicted by theoretical calculations are in satisfactory agreement with the experimental values, and the results obtained indicate the significance of solvent effects involved in this system.
文摘本文用 INDO 法研究了硫二氮杂环烷1.1—二氧化物模型分子（O<sub>2</sub>SN<sub>2</sub>H<sub>2</sub>）的几何结构、电子结构和化学链。结果不明,尽管某些参数与实验值和 ab initio 结果有较大的差异,但得到的分子构型为 OSO 平面垂直于 SNN 环平面及该分子主要通过2b1、3b1轨道成链的结果。在半经验近似条件下仍有参考价值。
文摘Ab initio SCF and Moller-Plesset correlation correction methods incombination with counterpoise procedure for BSSE correction have been applied to the theroeticalstudying of dimethylnitroamine and its dimers and trimers. Three optimized stable dimers and twotrimers have been obtained. The corrected binding energies of the most stable dimer and trimer werepredicted to be - 24.68 kJ/mol and - 47.27 kJ/mol, respectively at the MP2/6-31G ~*//HF/6-31G~*level. The proportion of correlated interaction energies to their total interaction energies for allclusters was at least 29.3 percent, and the BSSE of ΔE(MP2) was at least 10.0 kJ/mol. Dispersionand/ or electrostatic force were dominant in all clusters. There exist cooperative effects in boththe chain and the cyclic trimers. The vibrational frequencies associated with N―O stretches or wagsexhibit slight red shifts, but the modes associated with the motion of hydrogen atoms of the methylgroup show somewhat blue shifts with respect to those of monomer. Thermodynamic properties ofdimethylnitroamine and its clusters at different temperatures have been calculated on the basis ofvibrational analyses. The changes of the Gibbs free energies for the aggregation from monomer to themost stable dimer and trimer were predicted to be 14.37 kJ/mol and 30.40 kJ/mol, respectively, at 1atm and 298.15 K.
