芬氟拉明分子的密度泛函理论计算研究  

Study of Fenfluramine Molecule Based on the Density Functional Theory

作　　者：关力畅 冯磊 赵楠[1] 蒋雪梅 GUAN Li-chang;FENG Lei;ZHAO Nan;JIANG Xue-mei(Hunan Police Academy,Changsha 410138,China;Institute of Forensic Science of China,Beijing 100038,China;School of Criminal Investigation,People's Public Security University of China,Beijing 100091,China)

机构地区：[1]湖南警察学院,湖南长沙410138 [2]公安部鉴定中心,北京100038 [3]中国人民公安大学侦查学院,北京100091

出　　处：《光谱学与光谱分析》2025年第5期1270-1276,共7页Spectroscopy and Spectral Analysis

基　　金：国家重点研发计划基金项目(2023YFC3304104);湖南省教育厅科学研究项目(24B0954)资助。

摘　　要：因芬氟拉明(fenfluramine)可抑制食欲,不少商家非法将其添加在食物中进行售卖。食用芬氟拉明后,可引发肝脏功能异常、瓣膜性心脏病、原发性肺动脉高压等严重影响身体健康的疾病。因此研究芬氟拉明分子的结构、光谱、分子激发等具有十分重要的实际意义。基于密度泛函理论(DFT),使用B3LYP泛函6-311++G(2d,2p)基组,对芬氟拉明分子进行结构优化。在此基础上对该分子的结构、前线轨道、拉曼光谱、静电势能和紫外光谱开展了一系列详细的研究。获得了芬氟拉明分子的基本结构信息,其最高占据分子轨道和最低未占据分子轨道均为alpha+beta型轨道,能量分别为-6.25和-1.22 eV,能级差为5.03 eV。实验拉曼光谱中756.5和1003.5 cm^(-1)位置有两个强峰,其中756.5 cm^(-1)位置的强峰为CF3的对称变形振动和苯环上C═C的不对称变形振动;1003.5 cm^(-1)位置的强峰为苯环上C═C的对称变形振动,是间位双取代苯的特征谱带。实验拉曼光谱和计算拉曼光谱的线性拟合方程为y=0.988x+10.328,R2=0.999,呈现出较好的一致性。文章还讨论了芬氟拉明分子的表面静电势能分布和激发态性质。芬氟拉明分子共包含17个静电势能极大值点和12个静电势能极小值点。在-0.01~0.025 a.u.能量区间静电势能的表面积分布较为均匀。分子的紫外光谱主要由第1、2、3激发态决定,其中第2激发态的贡献率高达82.516%。利用空穴-电子分析法分析得出,S0→S1和S0→S2的激发类型均为胺基到苯环方向上的n-pi*电荷转移激发;S0→S3的激发类型是胺基到苯环方向的n-pi*电荷转移激发,同时伴随胺基到附近碳链的n-σ*局域激发。以上这些基础理论计算工作不仅为食品中非法添加芬氟拉明的检测提供了理论依据,还为研究其衍生物提供理论基础。Fenfluramine can inhibit appetite,so many merchants illegally added it to food for sale.After eating fenfluramine,it can cause liver dysfunction,valvular heart disease,primary pulmonary hypertension,and other diseases that seriously affect health.Therefore,studying fenfluramine molecules'structure,spectrum,and molecular excitation is of great practical significance.This work used the density functional theory(DFT)method with the B3LYP functional and 6-311++G(2d,2p)basis set for structural optimization.Furthermore,a series of studies were done on the structure,frontier orbits,Raman spectra,electrostatic potential,and UV spectra of the fenfluramine molecule.The basic structure information was obtained.The highest occupied orbital(HOMO)and the lowest unoccupied orbital(LUMO)were both alpha+beta orbits.The energy of HOMO,LUMO,and their energy gap was-6.25,-1.22 and 5.03 eV,respectively.There were two strong peaks at 756.5 and 1003.5 cm^(-1)in the experimental Raman spectrum.The strong peak at 756.5 cm^(-1)was the symmetric deformation vibration of CF3 and the asymmetric deformation vibration ofC═C on the benzene ring.The strong peak at 1003.5 cm^(-1)was the symmetrical deformation vibration ofC═C on the benzene ring,the characteristic band of meta-disubstituted benzene.The linear fitting equation of experimental Raman spectra and calculated Raman spectra isy=0.988x+10.328,R2=0.999,showing good consistency.This work also discussed the electrostatic potential and excited state properties of fenfluramine.The fenfluramine molecule contained 17 electrostatic potential energy maximum points and 12 electrostatic potential energy minimum points.The surface area distribution of electrostatic potential energy in the range of-0.01~0.025 a.u.was relatively uniform.The UV spectra were mainly determined by the first,second,and third excited states,and the contribution of the second excited state was as high as 82.516%.The electron excitation characteristics were studied by using hole-electron analysis.It could be found that S0

关 键 词：芬氟拉明分子 密度泛函理论 前线轨道 拉曼光谱 静电势能 紫外光谱 

分 类 号：O561[理学—原子与分子物理]