Ab initio calculations of electronic structure of the BaCs molecule: adiabatic potential energy curves, spectroscopic constants, spin–orbit effect and permanent and transition electric dipole moments

  • H. Ladjimi
  • M. Farjallah
  • R. Mlika
  • A. R. Allouche
  • H. BerricheEmail author
Regular Article


An ab initio approach based on effective core potentials (ECPs), core polarization potentials (CPPs) with three valence electrons and multireference configuration interaction (MRCI) level of calculation is used to determine the adiabatic potential energy curves, the spectroscopic constants and the permanent and transition electric dipole moments of the lowest doublet and quartet electronic states of BaCs. These sates are dissociating into the first six asymptotic limits of the alkali–alkaline earth molecule, BaCs. Only the ground state has been studied in the literature, and the comparison with the available results has shown a very good agreement. The spin–orbit interaction has been included in the next step of our calculation, and its effect on the potential energy curves and spectroscopic parameters on the Ω representation states has been thoroughly studied. Both relativistic and nonrelativistic calculations of permanent and transition dipole moments are also presented, which allows us to determine the influence of relativistic effects on the dipole moment.


BaCs Ab initio calculation Electronic structure Potential energy curves Spectroscopic constants Avoided crossing positions Dipole moments Spin–orbit coupling 



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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • H. Ladjimi
    • 1
  • M. Farjallah
    • 1
  • R. Mlika
    • 1
  • A. R. Allouche
    • 2
    • 3
  • H. Berriche
    • 1
    • 4
    Email author
  1. 1.Laboratory of Interfaces and Advanced Materials, Faculty of ScienceUniversity of MonastirMonastirTunisia
  2. 2.Université de LyonLyonFrance
  3. 3.CNRS, UMR 5579, LASIMUniversité Lyon 1VilleurbanneFrance
  4. 4.Department of Mathematics and Natural Sciences, School of Arts and SciencesAmerican University of Ras Al KhaimahRAKUAE

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