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arXiv · 1308.4242

Testing excited-state energy density functional and potential with the ionization potential theorem

M. Hemanadhan·Md. Shamim·Manoj K. Harbola
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Abstract

The modified local spin density functional and the related local potential for excited states is tested by employing the ionization potential theorem. The functional is constructed by splitting $k$-space. Since its functional derivative cannot be obtained easily, the corresponding potential is given by analogy to its ground-state counterpart. Further to calculate the highest occupied orbital energy $ε_{max}$ accurately, the potential is corrected for its asymptotic behavior by employing the van Leeuwen and Baerends correction to it. $ε_{max}$ so obtained is then compared with the $Δ$SCF ionization energy calculated using the MLSD functional. It is shown that the two match quite accurately.

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M. Hemanadhan, Md. Shamim, Manoj K. Harbola. 2013-08-20. Testing excited-state energy density functional and potential with the ionization potential theorem. https://doi.org/10.1088/0953-4075%2F47%2F11%2F115005

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