从头计算研究BCl^+基态和激发态的势能曲线和光谱性质  

Ab initio calculation on the potential energy curves and spectroscopic properties of the low-lying excited states of BCl^+

作　　者：于坤[1,2] 张晓美[2] 刘玉芳[2] 

机构地区：[1]兴义民族师范学院物理系,兴义562400 [2]河南师范大学物理与电子工程学院,新乡453007

出　　处：《物理学报》2013年第6期131-136,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11274096);贵州省科学技术基金(批准号:黔科合J字[2012]2325)资助的课题~~

摘　　要：基于相关一致极化4zeta(aug-cc-pVQZ)基组,应用量子化学从头计算中高水平的多参考组态相互作用方法计算了BCl+两个离解极限B+(1Sg)+Cl(2Pu)和B(2Pu)+Cl+(3Pg)的14个Λ-S态势能曲线.在计算中考虑了Davidson修正(+Q)和标量相对论效应,并首次在计算中考虑了BCl+的旋轨耦合效应,获得了由能量最低的4个Λ-S态分裂出的7个态.计算结果表明相同对称性的态的势能曲线存在着非常明显的避免交叉.通过分析Λ-S态的电子结构,得到了各态的电子跃迁特性,并确认了电子态的多组态性质.使用LEVEL程序通过求解径向的Schrdinger方程得到了束缚Λ-S和态的光谱参数De,Re,Te,ωe,ωeχe和Be.通过和已有的Λ-S态X2Σ+的实验数据进行对比发现,本文所得的计算结果与实验结果非常一致.而文中其他电子态的光谱参数均为首次报道.The high level quantum chemistry ab initio multi-reference configuration interaction method with reasonably large aug-cc-pVQZ basis sets is used to calculate the potential energy curves of 14 Λ-S states of BCl＋ radical correlated to the dissociation limit B＋（1Sg）＋Cl（2Pu） and B（2Pu） ＋Cl＋（3Pg）. In order to get the better potential energy curves, the Davidson correction and scalar relativistic effect are taken into consideration. The spin-orbit interaction is first considered, which makes the lowest 4 Λ-S states split to 7 Ω states. The calculational results show that the avoided crossing rule exists between the Ω states of the same symmetry. The analyses of the electronic structures of Λ-S states determine the electronic transition of each state and demonstrates that the Λ-S electronic states are multi-configurational in nature. Then the spectroscopic constants of the bound Λ-S and Ω states are obtained by solving the radial Schr？dinger equation. By comparison with experimental results, the spectroscopic constants of ground states are in good agreement with the observed values. The remaining computational results are reported for the first time.

关 键 词：势能曲线 光谱参数 多参考组态相互作用方法 旋轨耦合 

分 类 号：O561.1[理学—原子与分子物理]