Morse potential mixing

Other three-parameter functions can be used, and the same relationship between E and AE can be derived—e.g., Varshnis second potential function, which is a modified Morse potential (21) and Linnetts mixed exponential and inverse power of the internuclear distance (12). 

If this rule is applied together with the known dissociation limits, one obtains the qualitative picture given in Fig. 22 and realizes that standard Morse-type potentials are not realistic. The states actually calculated for the symmetry in Ne2 are contained in Fig. 23 and the expected behavior is fully borne out. Details of the other states and their mixing with one another can be found in the original reference. 

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