All literature on vibration-rotational and pure rotational transition energies for the X1Σ+ state of 4HeH+ , 3HeH+, 4HeD+, and 3HeD+ have been employed in a direct least-squares fit of the radially dependent Hamiltonian. The Born-Oppenheimer potential is represented by a modified Lennard-Jones function that provides for correct behavior in the near dissociation long-range region. Only 19 adjustable parameters were required to represent the 166 measured transition energies, which are reproduced al most to withi n the measurement accuracies. The fitted potential and Born-Oppenheimer breakdown functions are shown to be in good agreement with the results of ab initio calculations. The results are used to obtain high-order centrifugal distortion constants as well as level widths for quasi-bound levels.
|Number of pages||13|
|Journal||Journal of Molecular Spectroscopy|
|Publication status||Published - 1999|