Potential curves and rovibrational energies for electronic states of the molecular ion KCs+

Abstract

The KCs+ molecular ion potential curves are investigated over a wide range of internuclear distance for electronic states described in a 2Λ(+) representation (neglecting the spin-orbit effect) as well as in an Ω(+) representation (including the spin-orbit effect). This calculation has been done in a one active electron approach by using an ab initio method based on non-empirical pseudopotentials with core-valence effect taken into account through parameterized l-dependent polarization potentials. Gaussian basis sets have been used for both atoms, and spin-orbit effects have been taken into account through a semiempirical spin-orbit pseudopotential. The canonical functions approach is used to do a rovibrational study by calculating the eigenvalues Ev, the rotational constant Bv, the centrifugal distortion constants Dv (up to 106 vibrational levels), and the spectroscopic constants are deduced for six bound states. The permanent and transition dipole moment functions have been derived for transitions between the bound states 2 Σ+ and 2Π as well as the oscillator strengths for the transitions v = 0, 10, 20, and Δ v = 0, 1, 2, ..., 6. To the best of our knowledge neither theoretical nor experimental data are available in the literature for the molecular ion KCs+. Extensive tables of Ev, Bv, Dv, and the energy values versus internuclear distance are displayed at the following address: http://hplasim2.univ-lyon1.fr/allouche/kcsplus.html. PACS Nos.: 33.15Dj, 33.20wr