<div dir="ltr">Dear all, <div><br></div><div>I am studying a BaFeO3 perovskite structure, and I am struggling with the convergence, primarily the Ecut WFC convergence. </div><div><br></div><div>So far I have used a variety of PPs for this structure, yet cannot get a sensible convergence for the Ecut Wfc, please see my convergence data below: </div>
<div><br></div><div>Pseudopotentials: </div><div><br></div><div><b>Config 1:</b></div><div><div> Ba Ba.pbe-spn-rrkjus_psl.1.0.0.UPF</div><div> Fe Fe.pbe-spn-rrkjus_psl.1.0.0.UPF</div><div> O O.pbe-n-rrkjus_psl.1.0.0.UPF</div>
<br>
</div><div>Ecut Convergence: </div><div>
<p class=""><span class="">wfc=[</span>50.0<span class="">, </span>60.0<span class="">, </span>70.0<span class="">, </span>80.0<span class="">, </span>90.0<span class="">, </span>100.0<span class="">, </span>110.0<span class="">]</span></p>
<p class=""><span class="">Energy=[-</span>407.95822783<span class="">, -</span>407.9701389<span class="">, -</span>407.97593501<span class="">, -</span>407.98115532<span class="">, -</span>407.98307678<span class="">, -</span>407.98336097<span class="">, -</span>407.98358971<span class="">, -</span>407.98436114<span class="">]</span></p>
<p class=""><span class=""><b>Config 2:</b> </span></p><p class=""> Ba Ba.pbe-nsp-van.UPF</p><p class=""> Fe Fe.pbe-spn-rrkjus_psl.0.2.1.UPF</p><p class=""><span class=""></span></p><p class=""> O O.pbe-n-rrkjus_psl.0.1.UPF</p>
<p class="">WFC=([<span class="">30.0</span>, <span class="">40.0</span>, <span class="">50.0</span>, <span class="">60.0</span>, <span class="">70.0</span>, <span class="">80.0</span>, <span class="">90.0</span>, <span class="">100.0</span>, <span class="">110.0, </span>120.0])</p>
<p class=""><span class="">
</span></p><p class=""><span class="">energy = ([-</span>445.36783430<span class="">, -</span>445.74664179<span class="">, -</span>445.82508351<span class="">, -</span>445.82904841<span class="">, -</span>445.83336392<span class="">, -</span>445.83728481<span class="">, -</span>445.83834745<span class="">, -</span>445.83834171<span class="">, -</span>445.83853799, -445.83894056])</p>
<p class=""><span class=""><br></span></p><p class=""><span class="">I have read several papers where similar studies have been done using Ecut_wfc as low as 40Ry which confuses me greatly. For all calc I used Ecut_rho=8* Ecut_wfc, with a converged K-point mesh of (8x8x8), yet I am not sure whether there is something my input (please see below). I have ran calcs for both spin polarised and non polarised, however this has not changed the convergence. I would greatly appreciate an insight into whether a convergence of 100Ry is acceptable for US pseudos? </span></p>
<p class=""><span class=""><br></span></p><p class=""><span class="">Any help will be much appreciated. </span></p><p class="">Kind Regards, <br></p><p class=""><span class=""><br></span></p><p class="">Zarah Baiyee<br></p>
<p class="">PhD candiate, HKUST<br></p><p class=""><span class=""><br></span></p><p class=""> &system</p><p class=""> ibrav = 0, nat= 5, ntyp= 3, </p><p class=""> ecutwfc = 100.0, ecutrho = 800.0</p><p class="">
occupations='smearing', smearing='gaussian', degauss=0.02</p><p class=""> /</p><p class=""> &electrons</p><p class=""> diagonalization='cg'</p><p class=""> conv_thr = 1.0e-6</p><p class="">
mixing_beta=0.2</p><p class="">/</p><p class="">CELL_PARAMETERS (bohr)</p><p class="">7.6 0.0 0.0</p><p class=""> 0.0 7.6 0.0</p><p class=""> 0.0 0.0 7.6</p><p class="">ATOMIC_SPECIES</p><p class=""> Ba 137.32 Ba.pbe-nsp-van.UPF</p>
<p class=""> Fe 55.84 Fe.pbe-spn-rrkjus_psl.0.2.1.UPF</p><p class=""> O 15.99 O.pbe-n-rrkjus_psl.0.1.UPF</p><p class="">ATOMIC_POSITIONS (crystal)</p><p class=""> Ba 0.000000 0.000000 0.000000 </p><p class=""> Fe 0.500000 0.500000 0.500000</p>
<p class=""> O 0.500000 0.500000 0.000000</p><p class=""> O 0.500000 0.000000 0.500000</p><p class=""> O 0.000000 0.500000 0.500000</p><p class="">K_POINTS (automatic)</p><p class=""><span class=""></span></p><p class="">
8<span class="" style="white-space:pre"> </span>8<span class="" style="white-space:pre"> </span>8<span class="" style="white-space:pre"> </span>0<span class="" style="white-space:pre"> </span>0<span class="" style="white-space:pre"> </span>0</p>
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