Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (12): 123103-123103.doi: 10.1088/1674-1056/22/12/123103

• ATOMIC AND MOLECULAR PHYSICS • 上一篇    下一篇

Ab initio MRCI+Q study on potential energy curves and spectroscopic parameters of low-lying electronic states of CS+

李瑞a, 魏长立b, 孙启响b, 孙二平b, 金明星b, 徐海峰b, 闫冰b   

  1. a Department of Physics, College of Science, Qiqihar University, Qiqihar 161006, China;
    b Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
  • 收稿日期:2013-03-14 修回日期:2013-05-06 出版日期:2013-10-25 发布日期:2013-10-25
  • 基金资助:
    Project supported by the National Basic Research Program of China (973 Program) (Grant No. 2013CB922200), the National Natural Science Foundation of China (Grant Nos. 11034003, 11074095, and 11274140), the Natural Science Foundation of Heilongjiang Province, China (Grant No. QC2011C092), and the Scientific Research Fund of Heilongjiang Provincial Education Department, China (Grant No. 12531751).

Ab initio MRCI+Q study on potential energy curves and spectroscopic parameters of low-lying electronic states of CS+

Li Rui (李瑞)a, Wei Chang-Li (魏长立)b, Sun Qi-Xiang (孙启响)b, Sun Er-Ping (孙二平)b, Jin Ming-Xing (金明星)b, Xu Hai-Feng (徐海峰)b, Yan Bing (闫冰)b   

  1. a Department of Physics, College of Science, Qiqihar University, Qiqihar 161006, China;
    b Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
  • Received:2013-03-14 Revised:2013-05-06 Online:2013-10-25 Published:2013-10-25
  • Contact: Li Rui, Yan Bing E-mail:lirei01@163.com;yanbing@jlu.edu.cn
  • Supported by:
    Project supported by the National Basic Research Program of China (973 Program) (Grant No. 2013CB922200), the National Natural Science Foundation of China (Grant Nos. 11034003, 11074095, and 11274140), the Natural Science Foundation of Heilongjiang Province, China (Grant No. QC2011C092), and the Scientific Research Fund of Heilongjiang Provincial Education Department, China (Grant No. 12531751).

摘要: Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states have not been well investigated. In this paper, the electronic states of CS+ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects (scalar plus spin–orbit coupling). The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS+ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS+ are illuminated. Finally, the single ionization spectra of CS (X1Σ+) populating the CS+(X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+) states are simulated. The vertical ionization potentials for X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV~0.2 eV.

关键词: potential energy curves, spin–, orbit coupling, carbon monosulfide molecular ion (CS+), ionization spectrum

Abstract: Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states have not been well investigated. In this paper, the electronic states of CS+ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects (scalar plus spin–orbit coupling). The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS+ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS+ are illuminated. Finally, the single ionization spectra of CS (X1Σ+) populating the CS+(X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+) states are simulated. The vertical ionization potentials for X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV~0.2 eV.

Key words: potential energy curves, spin–orbit coupling, carbon monosulfide molecular ion (CS+), ionization spectrum

中图分类号:  (Potential energy surfaces for excited electronic states)

  • 31.50.Df
31.15.aj (Relativistic corrections, spin-orbit effects, fine structure; hyperfine structure) 31.15.ag (Excitation energies and lifetimes; oscillator strengths)