He_2^+和He_2^(++)分子离子基态和激发态的特性研究  

Study on the Characteristics of the Ground States and Excited States of He_2^+ and He_2^(++) Molecule Ions

作　　者：张云光[1] 高涛[1] 李桂霞[1] 张传瑜[1] 陈东[1] 朱正和[1] 

机构地区：[1]四川大学原子与分子物理研究所,成都610065

出　　处：《物理化学学报》2006年第7期780-785,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(10376022)资助项目

摘　　要：采用SAC/SAC-CI方法在CC-PV5Z基组下,计算研究了He2+、He+2+的基态及低激发态的分子特性,给出了其基态和一些激发态的势能函数和光谱数据(Be、!e、"e和"e#e).从群论出发推导了相应状态的离解极限;与已有实验结果的He+2(X2$+u)相比,计算结果令人满意.还计算了激发态2%u、4$+u和4%g的结构与光谱数据.对于He+2+,计算的九个电子态中只有三个态(X1$g+、1$g+和1$u+)属束缚态,并得到了其光谱常数.用价键理论模型的不相交规则对He+2+基态的势能曲线极大点产生的原因做了较好的分析.The molecule structures for the ground and low-lying states of He2^＋ and He2^＋＋ are calculated using the SAC/ SAC-CI with the basis set CC-PV5Z. The analytical forms of potential energy function are least-squared-fitted from the potential energy and the corresponding spectroscopic data are derived out. For He2^＋, the obtained spectroscopic data of X^2∑u^＋ are in well agreement with the experimental data and the results for the excited states 2∏u, ^4∑u^＋and ^4∏g are worked out for the first time. For HeT, the results indicate that only the ground state X^1∑g^＋ and excited states ^1∑g^＋, ^1∑u^＋ among the nine calculated states are bound states. The spectroscopic constants corresponding to these three states are worked out, and the origin of the energy barriers in the ground states X^1∑g^＋ energy curve has been explained using the avoided crossing rules of valence bond model.

关 键 词：激发态 势能函数 光谱数据 He2^+ He2^++ 

分 类 号：O641.1[理学—物理化学]