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Recent work has shown the success of the semiempirical and zero-free-parameter form of the ligand field model as applied to diatomic rare earth oxides and $fluorides1$. We report here the results of the semiempirically calculated d-5 energy shift of the center of gravity of the appropriate configurations of $Ln2+$ and $Ln+$,$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ which is relevant to the electronic structure of LnO and $LnF3$.[FIGURE] \begin {center}\begin {tabular}{@{}lccrcccc@{}} Ln &\multicolumn{2}{c}{free ion} &$Ln2+$ &\multicolumn{2}{c}{molecule} &LnO &d-s stabil.\ & & &differ & & &differ &energy$(cm-1)$\ La &$961$ &$13591$ &$-12630$ &$11950$ &$0$ &$11950$ &$24600$\ Cd &$4939$ &$10225$ &$-5276$ &$11300$ &$800$ &$10500$ &$15800$\ Lu &$7472$ &$0$ &$7472$ &$19800$ &$0$ &$195800$ &$12300$\ & &\multicolumn {2}{c}{Ln+} & & &LnF &\ & & &differ & & &differ &\ Ba &$5354$ &$0$ &$5354$ &$11500$ &$0$ &$11500$ &$6100$\ Eu &$13393$ &$730$ &$12663$ &$17000$ &$620$ &$16380$ &$3700$\ & & & & & & &\ La &$4593$ &$7394$ &$-2801$ &$4600$ &$0$ &$4600$ &$7400$\ Cd &$5474$ &$3444$ &$2030$ &$6500$ &$0$ &$6500$ &$4500$ \end{tabular}\end {center} The d-5 stabilization energy in LnO and LnF molecules decreases with increasing atomic number.