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<p>Dear All,</p>
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<p>I am currently attempting to perform Wannierization for a relatively large supercell comprising 96 atoms. In my DFT calculations using VASP, my structure involves repeating MAPbI3 units (8 times). For the KPOINTS setting, I have employed the gamma point,
and in the corresponding wannier input file, I have set "gamma_only = true". However, upon enabling the gamma_only option, I encountered the following error message:</p>
<p><span>"wannier90.mmn has not the right number of nearest neighbours".</span></p>
<p>To generate the initial wannier90 files, I incorporated the following commands into my INCAR file, which successfully produced the .amn, .mmn, .eig, and .win files:</p>
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<div style="margin-top:0;margin-bottom:0;"><span>LWANNIER90 = .TRUE.</span><br>
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<div>NUM_WANN = 104<br>
<span class="highlight" id="0.1093365828327646" name="searchHitInReadingPane">WANNIER</span>90_WIN = "</div>
<div>gamma_only = true<br>
Begin Projections<br>
Pb:l=1</div>
<div>Pb:l=0<br>
I:l=1<br>
End Projections<br>
"</div>
<div>My .mmn file started with:<br>
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<div>File generated by VASP: unknown system <br>
252 64 6<br>
1 2 0 0 0<br>
0.909230482043 0.409856179950<br>
-0.000126326113 -0.000013000425</div>
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<div><span>I attempted the LSCDM approach along with random projections; but, I encountered the same error.</span><br>
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<div>Can you please help me with this issue?<br>
<span>Additionally, I would appreciate your insights on whether it is meaningful to carry out a DFT calculation with a single KPOINT (gamma point), while performing the subsequent Wannierization with kpoints set at 2 2 2 or 4 4 4, etc.</span><br>
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<p><span style="font-size:12pt;" id="divtagdefaultwrapper">Thank you very much in advance for your support,
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<div style="margin-top:0;margin-bottom:0;">Kind regards,</div>
<div style="margin-top:0;margin-bottom:0;">Sadegh Talezadeh</div>
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