Molecular Rydberg states expression

Most treatments of molecular Rydberg states in the case (d) and (e) limits rest on a crucial simplification of the possible coupling schemes among the ion-core, Rydberg electron, and core+Rydberg electron angular momenta. When S+ = 0 or when S+ = 1/2 and A+ = 0, the case (d) and (e) basis functions become very similar. For example, if 5I+ = 0, then N+ = J+ and the case (d) and (e) basis functions take on Watson s (b+, d) and (b+, e) forms, respectively, and the two basis sets are related by a simple case (e) <— (d) transformation for the Rydberg electron, expressed in terms of 6-j coefficients,... 

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