The Scheme of Virtual Charges

So as to describe correctly the asymptotic behavior of a(e), Constanciel and Tapia [21] have taken the following empiric relationship  

Then Eq. (3.17) will coincide with the rigorous Born expression  

The virtual charges scheme is better substantiated than the Klopman model since in it both the charge and the energy depend on in a noncontradictory manner. 

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