Accurate analytic approximations for the rotating Morse oscillator: Energies, wave functions, and matrix elements

The assumption that the effective potential for a rotating Morse oscillator always retains a Morse form enables approximate, analytic expressions to be derived for the energy levels, wave functions, and for matrix elements of positive powers of the internuclear separation of a rotating Morse oscillator. Comparison with exact numerical, and with experimental results, shows that the formulas presented are accurate, even for highly excited vibration-rotation states.