Photoassociation spectrum for the Hg₂(X0_g⁺) → Hg₂(D1_u) transition: The Hund's (C) case

Potential curves for the lower unbound Hg₂(X0_g⁺) state and the upper Hg₂(D1_u) state of the mercury dimer are determined by multiply repeating calculations of the desired spectrum and comparing the results obtained with the experimental data. Initial Morse potentials are supplied with patches, making the potentials steeper on one of its wings and more flattened on the other wing compared to the usual Morse potential. The values of ω_e and ω_ex_e for the Hg₂(X0_g⁺) and Hg₂(D1_u) states are determined according to several lowest vibrational states of the terms. Coordinates of turning points are also given for the corresponding states. These data seem to be useful in studying the mercury dimer by the traditional method with a low vibrational excitation.