C_4^(2+)分子的E_ub_(2g)系统的杨-泰勒畸变及其各向异性现象  

The Jahn-Teller effect and anisotropic phenomena of the E_ub_(2g) system for C_4^(2+) molecules

作　　者：冯胜奇[1] 

机构地区：[1]韩山师范学院物理与电子工程系,广东潮州521041

出　　处：《西北师范大学学报（自然科学版）》2011年第5期35-39,共5页Journal of Northwest Normal University(Natural Science)

基　　金：广东省自然科学基金资助项目(34613)

摘　　要：依据杨-泰勒效应理论和量子理论探讨了C24+分子的Eub2g系统的杨-泰勒畸变与各向异性现象,构建了Eub2g系统的电声耦合哈密顿量,并借助么正平移变换求出了畸变之后的系统电子基态与激发态及其能量.结果表明,畸变导致系统在其势能面上形成了两个具有D2h对称性势阱;无论系统处在哪一个势阱中,系统的二重简并的电子基态能级都将发生分裂.经过杨-泰勒畸变,C24+分子将从D4h对称性降低到D2h对称性,同时C24+分子的振动频率发生分解,频率的分解意味着C24+分子在平面上的各向同性遭到破坏而呈现出各向异性.Based on Jahn-Teller effect theory and quantum theory,the Jahn-Teller effect and anisotropic phenomena of the Eub2g system for C2＋4 molecules with D4h symmetry are discussed in this paper.The vibronic Hamiltonian of the Eub2g system is constructed.The ground electronic states and their energies of the system in each minimum are obtained using unitary shift transformation,and the corresponding excited electronic states and their energies in each minimum are also derived further.It is found that there are two potential energy minima with D2h symmetry on the potential energy surface of the system because of the vibronic coupling.No matter which minimum the system is in,the original ground energy level of the system is split into two energy levels after the distortion.The distortion should lead the symmetry of C2＋4 molecules to be lowered to D2h from D4h.The vibrational frequencies of C2＋4 molecules are split because of the distortion,the isotropy of C2＋4 molecules is destroyed and its anisotropy should appear after the Jahn-Teller distortion.

关 键 词：电声耦合 杨-泰勒畸变 能级分裂 频率分解 各向异性 

分 类 号：O561.1[理学—原子与分子物理] O413.1[理学—物理]