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
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.