CH_(4)分子在外电场作用下的结构和解离特性研究  

Spectrum and Dissociation Properties of CH_(4) in External Electric Field

作　　者：唐臻 陈晓宇[1] 万文梓 邹勇 吴建光[1] 马建军[1] TANG Zhen;CHEN Xiao-yu;WAN Wen-zi;ZOU Yong;WU Jian-guang;MA Jian-jun(Anhui University of Technology,Maanshan,Anhui,243000,China)

机构地区：[1]安徽工业大学,马鞍山安徽243002

出　　处：《凯里学院学报》2023年第6期18-26,共9页Journal of Kaili University

基　　金：安徽高校自然科学研究重点项目(KJ2021A0388)。

摘　　要：采用B3LYP/6-311++G**方法和基组对外电场下CH_(4)分子的性质进行了一系列的研究,包括分子的基态结构、电偶极矩、总能量、HOMO能级、LUMO能级、能隙Eg、红外与拉曼光谱性质和C-H键的解离特性.结果表明:随着加在C-H键轴方向的外电场增加,CH_(4)分子中的C-H键长明显变长,能隙随着外电场的增加而减小;外电场对分子的红外与拉曼振动频率和振动强度都有重大影响.CH_(4)分子的红外和拉曼光谱在外电场下都发生了重叠谱线的分裂和红移现象.随着外加电场的增强,分子中C-H键的势能曲线发生变化,势阱深度随外电场强度的增大而减小直至消失,分子趋向于解离.Utilizing density function theory(DFT),We study the structure and spectrum properties of CH_(4) molecules in the external electric field at the B3LYP/6-311++G**,including the equilibrium structure,electric dipole moment,total energy,HOMO energy level,LUMO energy level,energy gap,infrared and Raman spectrum and dissociation of C-H bond.The results show that the C-H bond length extends and the electric dipole moment increases with the increase of electric field intensity,while the energy gap Eg decreases with increasing the electric field intensity.The external electric field influences the absorption intensity of infrared and Raman spectrum,the splitting of spectral lines and red-shift of infrared and Raman spectrum occur under the external electric field.Discussing the mole⁃cule dissociation in the external electric field,the potential curve of C-H bond changes with incre⁃ment of the electric field strength,the potential well depth decreases with the increase of the external electric field and gradually vanishes,the CH_(4) molecule tends to dissociation.

关 键 词：甲烷 外电场 光谱性质 降解 

分 类 号：O561[理学—原子与分子物理]