Theoretical calculation of the low laying electronic states of the molecular ion KH+

Using an ab initio method the potential energy has been calculated for the 25 lowest molecular states of symmetries 2Σ+, 2Π, 2Δ for the molecular ion KH+. The calculation is based on nonempirical pseudopotentials and parameterized ℓ-dependent polarization potentials. Gaussian basis sets have been used for both atoms. The spectroscopic constants for 18 electronic sates have been calculated by fitting the calculated energy values to a polynomial in terms of the internuclear distance R. Through the canonical functions approach the eigenvalue Ev, the abscissas of the corresponding turning points (Rmin and Rmax) and the rotational constants Bv have been calculated up to 24 vibrational levels for the considered bound states. The comparison of the present results with those available in literature shows a very good agreement.