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<span style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important">Dear all,</span><br style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255)">
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<span style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important">I would like to calculate the effect of charge doping on the lattice constant of a 2d metallic material. </span></div>
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<span style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important">According to the manual, we can do this by changing the keywords "tot_charge" to add or remove charges from the neutral system. </span><span style="font-family: Arial; font-size: 15px;">The
excess charge in perfect single layer 2d materials will somehow be delocalized and is compensated by a uniform background opposite charge. But in this case, as I understand, because of the periodic boundary condition, the total energy would depend on the width
of the vacuum space. Am I right? </span></div>
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<span style="font-family: Arial; font-size: 15px;">If yes, my second question is if I can do the lattice optimization of charged slab systems by calculating the Energy vs. lattice constant curve with a fixed width of vacuum space. </span></div>
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<div style="color: rgb(0, 0, 0);">I also notice that in Quantum Espresso there are two options (<span style="font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, "Helvetica Neue", sans-serif; background-color: rgb(255, 255, 255); display: inline !important">"2D"
and "esm"</span>) for the tag "assume_isolated" to deal with charged slab calculation. Do I need to switch on this tag? Which option, <span style="font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, "Helvetica Neue", sans-serif; background-color: rgb(255, 255, 255); display: inline !important">"2D"
or "esm",</span> is the better to serve the purpose?</div>
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<div style="color: rgb(0, 0, 0);">Any comments and suggestions would be appreciated. Thank you in advance!<br style="background-color: rgb(255, 255, 255);">
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<span style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important;">Best,</span><br style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255)">
<span style="font-family: Arial; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important;">Bin</span><br>
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