CH自由基在外电场中的分子结构和势能函数  

Molecular structure and potential energy function of CH molecule under external electric field

作　　者：伍冬兰[1] 涂娟[1] 万慧军[1] 谢安东[1] 阮文[1] 张新琴[1] 

机构地区：[1]井冈山大学数理学院,吉安343009

出　　处：《原子与分子物理学报》2014年第2期197-201,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(11147158;11264020);江西省自然科学基金(2010GQW0031);江西省教育厅科技项目(GJJ12483;GJJ12463;GJJ11540)

摘　　要：运用密度泛函B3P86方法,结合Dunning的相关一致五重基cc-PV5Z,获得了CH自由基分子在不同外电场中的键长、偶极矩和振动频率等物理性质参数.通过分析物理性质参数的变化,判断离解电场所处的范围,设置合适的参数扫描该范围的单点能获得势能曲线.结果表明物理性质参数和势能值随外电场的变化而变化,且反向电场中变化幅度较大.利用Morse势模型拟合无外场下势能函数,得到的拟合参数与实验值吻合较好,采用偶极近似构建外电场下的势能函数模型,编制程序拟合对应的势能函数,得出拟合参数,进而计算临界离解电场参量,结果与数值计算值较为一致,说明构建的模型是可靠和准确的.这为分析外场下分子光谱、动力学特性和分子Stark效应冷却囚禁提供重要的理论和实验参考.Using density functional B3P86/cc-PV5Z method,the geometric structure of CH molecule under different external electric fields are optimized,and obtained the bond lengths,dipole moments,vibration frequencies and other physical properties parameters.On the basis of setting appropriate parameters to scan single point energies,and getting the potential energy curves of different external fields.The results show physical properties parameters and potential energy values will change with the external electric fields change,especially at reverse direction electric fields.The potential energy function without external electric field is fitted by Morse potential,and gotten the fitting parameters,which are good agreement with experimental values.In order to get the critical dissociation electric parameter,the dipole approximation is adopted to construct potential model,then put the model to fit the corresponding potential energy curve of external electric field.It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation,so that the constructed model is reliable and accurate.These will provide important theoretical and experimental reference for more studying the molecular spectroscopy,dynamics and molecular cooling with Stark effect.

关 键 词：CH分子 势能函数模型 外电场 

分 类 号：O561.3[理学—原子与分子物理]