The adsorption sites and diffusion mechanism of CO2 molecules in the flexible Zn（MeIM）2 （MeIM=2-methylimidazole） （ZIF-8） have been investigated by grand canonical Monte Carlo and molecular dynamics simulations. ...The adsorption sites and diffusion mechanism of CO2 molecules in the flexible Zn（MeIM）2 （MeIM=2-methylimidazole） （ZIF-8） have been investigated by grand canonical Monte Carlo and molecular dynamics simulations. A reasonable time correlation function is for the first time constructed to explore the mean residence time of CO2 molecules in the ZIF-8 cages, suggesting that C02 molecules can remain in the same cage for up to several tens of picoseconds. Furthermore, we find that the mean residence time almost linearly increases with the increasing pressure （or loading） at 273 and 298 K.展开更多
The infrared （IR） spectra of the N-methylacetamide molecule in water are calculated by using the MD simulation with high-level QM]MM corrections. The B3LYP and MP2 levels with 6-31 I＋＋G＊＊ basis set are used for ...The infrared （IR） spectra of the N-methylacetamide molecule in water are calculated by using the MD simulation with high-level QM]MM corrections. The B3LYP and MP2 levels with 6-31 I＋＋G＊＊ basis set are used for the QM region, respectively, Our results show all IR spectra at the B3LYP level are well consistent with the corresponding MP2 results. A dynamical charge fluctuation is observed for each atom along the simulation trajectories due to the electrostatic polarization （EP） effects from surrounding solvent environment, We find that the QM/MM corrected IR spectra satisfactorily reprodnce the experimental vibrational features of amide 1-11I modes.展开更多
文摘The adsorption sites and diffusion mechanism of CO2 molecules in the flexible Zn（MeIM）2 （MeIM=2-methylimidazole） （ZIF-8） have been investigated by grand canonical Monte Carlo and molecular dynamics simulations. A reasonable time correlation function is for the first time constructed to explore the mean residence time of CO2 molecules in the ZIF-8 cages, suggesting that C02 molecules can remain in the same cage for up to several tens of picoseconds. Furthermore, we find that the mean residence time almost linearly increases with the increasing pressure （or loading） at 273 and 298 K.
基金supported by the Natural Science Foundation of China(Nos.21306070 and 20966003)the Science&Technology Programs of Education Department of Jiangxi Province(No.GJJ12191)
文摘The infrared （IR） spectra of the N-methylacetamide molecule in water are calculated by using the MD simulation with high-level QM]MM corrections. The B3LYP and MP2 levels with 6-31 I＋＋G＊＊ basis set are used for the QM region, respectively, Our results show all IR spectra at the B3LYP level are well consistent with the corresponding MP2 results. A dynamical charge fluctuation is observed for each atom along the simulation trajectories due to the electrostatic polarization （EP） effects from surrounding solvent environment, We find that the QM/MM corrected IR spectra satisfactorily reprodnce the experimental vibrational features of amide 1-11I modes.
