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The hydrogen partition function is then calculated from (5.7). The remaining hydrogen partition functions are evaluated as described in the discussion of the four hydrogen reactions in Chapter V.

        Step 2.--Depending on the pressure and temperature, the low, intermediate, or high temperature equations are used to compute the plasma composition by iterating on the electron concentration until the mixing ratio converges to the specified value.

        Step 3.--The electron density from Step 2 is used to recalculate the hydrogen cut-off quantum numbers from (5.8). The hydrogen and uranium densities from Step 2 are used to calculate the ionization potential lowering using (4.38). The uranium cut-off quantum numbers are then estimated from (4.43).

        Step 4.--Using the initial ionizations potentials in each iteration, Steps 2 and 3 are repeated r times until the electron density converges to N (r) - (r-)     E e                                               e5
and the uranium cut-off quantum numbers converge to n(r) (i) - n(r-l) (i) < 1 for all i.

        Step 5.--The ionization potential is corrected using (4.38) and Step 2 is repeated to give the final values for the mixed plasma composition.