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Dear QE users,</div>
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I would like to calculate the adsorption energy of a negative anion NO3- with a positive slab (The total system is neutral). I cannot use the convention formula Eds = E(slab+anion) - E(slab) - E(anion) because of the charge compensation when calculating the
energy of charged slab and charge adsorbate. </div>
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As the total system (<span style="background-color:rgb(255, 255, 255);display:inline !important">slab+anion</span>) is neutral, I wonder if it is possible to just move the <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">molecule
far away from the slab (make sure that vacuum in z-direction is large enough), and calculate the energy difference i.e.,
</span><span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">one of them the molecule is far away from the surface and in the other one the molecule adsorbed on the surface.</span></div>
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Best regards</div>
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Nam</div>
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