诺氟沙星的密度泛函研究

Density functional study of norfloxacin

摘要:

以诺氟沙星为研究对象，采用密度泛函理论的B3LYP/6-311+G(d,p)方法，进行分子结构全优化，并对红外光谱(IR)和拉曼光谱(Raman)、前线轨道(最高占据轨道HOMO、最低空轨道LUMO)、净电荷分布进行了量子力学计算。根据红外光谱(IR)和拉曼光谱(Raman)的计算结果，对振动模式进行了指认；根据前线轨道(HOMO、LUMO)、净电荷分布的计算结果，讨论了诺氟沙星的HOMO、LUMO和分子表面电势的特点。采用密度泛函理论的B3LYP/6-311+G(2d,p)方法，进行分子结构全优化，使用GIAO方法计算得到核磁共振谱(NMR)，并对谱图数据进行了分析讨论。

Abstract:

The molecule of norfloxacin was investigated with the density functional theory (DFT), and the molecular geometry was optimized by utilizing B3LYP method at the levels of 6-311+G(d,p). Based on the optimized geometry, the infrared absorption spectra (IR) and Raman scattering spectra (Raman), the frontier molecular orbital and the net charge distribution were calculated by the means of quantum mechanics. According to the calculation results of the infrared absorption spectra (IR) and Raman scattering spectra (Raman), characteristic vibrational frequencies of norfloxacin molecule were assigned. Based on the calculation results of the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and the net charge distribution, the characteristics of the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and the potential energy surface were discussed. Based on the molecular geometry was optimized by utilizing B3LYP method at the levels of 6-311+G(2d,p), and applying the theory of GIAO, the nuclear magnetic resonance (NMR) was obtained and the spectral data were analyzed and discussed.