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in the selective radial expectation moments 〈 r − $^{2}$〉 , 〈 r − $^{1}$〉 , 〈 r $^{1}$〉 and 〈 r $^{2}$〉 values of these 6 states of Li $^{−}$, Be− as compiled in Table III. Some of these quantities have been recently reported in the VMC calculation of [8], quoted in parentheses for comparison. Generally there is good agreement between our results with them, especially for the negative moments and discrepancy tends to increase for the positive moments. However the general trend is similar as theirs. The negative expectation values of Li − are reduced for both the excited states ( $^{5}$P $^{e}$, $^{5}$S $^{e}$) compared to the ground state, and having closer values to each other, due to the close resemblance of their corresponding radial densities close to the nucleus. $^{5}$P e state with lowest energy showing larger 〈 r − $^{2}$〉 and 〈 r − $^{1}$〉 than the $^{5}$S $^{o}$. The positive moments however correspond more to the charge densities at intermediate-to-large distances, and show complicated behavior. For Be $^{−}$, the negative moments are smaller for $^{6}$S o term compared to the quartet S and P terms, with the latter two having similar values, as they have the same [He] core. As in Li $^{−}$, the P state (with lower energy) gives higher values of the negative moments compared to the S state. 

## IV. CONCLUSION 

A density-based formalism was employed for the first time to calculate the state energies, radial density as well as selected density moments of three excited states of Li − and Be − in addition to the ground state of the former. A work-function-based exchange potential plus the nonlinear LYP correlation potential was used, while the resulting KS equation was numerically solved by an optimal, nonuniform, spatial GPS discretization scheme accurately. 

Additionally two transition wavelengths of Li $^{−}$, Be− were computed. Comparison with the existing theoretical as well as experimental data were made. For all practical purposes our X-only results are of HF quality and with correlation included, they produce excellent 

