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for the reaction Ui+ -U(i+l)+ where

         E. = uncorrected ionization potential AE. = lowering of ionization potential

Griem (44) has used the Debye-fHuckel theory (36) for ionized gases to obtain an analytical expression for the amount of potential lowering. For an uranium plasma with a maximum of twelve degrees of ionization, the potential lowering is given by 13
     AEi = 2(Zi + l)e3(Tr/kT)l/2(Ne + 7   g2Ni)-1/2 i=2
                                                    (4.38)

where

        Zi = charge of i-th ion

        e    electrostatic charge of the electron

        N = electron density N. = i-th ion density

Cut-off Quantum Number as a Function of Effective Ionization Potential

        The electronic partition function of uranium was given by
                00

          u.=      g g  e- Xij/kT                   (435)
               3=0