<div dir="ltr"><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">Dear all users,</p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br></p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">I encountered one problem when doing consistency test of parameters of phonon frequencies at Gamma point, shown as in the Table below, in which are the lowest phonon frequencies of Gamma point after applying ASR.<br></p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br></p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">From the table, we can see that for smearing (S (Ry)), the frequency converge well except smearing=0.125Ry, which is understandable because of the too large value of smearing.  The problem part is the convergence of ENCUT. In general, the larger ENCUT is, the better results are. But for higher ENCUT, it does not converge. Could anyone give me any instructions why the convergent of ENCUT is like this, I will appreciate it.</p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br></p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">The K-mesh is 4*4*4 which turns out OK for the system and all of structures are well relaxed under the parameters. And the calculations are carried out by Quantum Espresso-5.2.<br></p><p style="margin-top:0px;margin-bottom:0px;color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><br></p><table cellpadding="0" cellspacing="0" width="575" class="gmail-m_-8401468728650448730gmail-ms-rteTable-lightlines" style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px;width:431pt;border-collapse:collapse;border:1px solid transparent"><colgroup><col width="63" style="width:47pt"><col width="64" span="8" style="width:48pt"></colgroup><tbody><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableEvenRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td height="20" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" width="63" style="height:15pt;width:47pt"> <br></td><td colspan="8" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines" width="512" style="width:384pt">ENCUT/(Ry)</td></tr><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableOddRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td height="20" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" style="height:15pt"> </td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines"> </td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">40</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">45</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">50</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">55</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">60</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">65</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">70</td></tr><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableEvenRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td rowspan="4" height="80" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" style="height:60pt">S<br>(Ry)</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">0.005</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-67.2</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.37</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.37</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-127.84</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.28</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.25</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-87.94</td></tr><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableOddRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td height="20" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" style="height:15pt">0.010</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-66.91</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.37</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.37</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-127.88</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.26</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.25</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-87.88</td></tr><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableEvenRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td height="20" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" style="height:15pt">0.025</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-67.57</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.35</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.38</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-127.69</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-0.31</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-0.26</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-87.93</td></tr><tr height="20" class="gmail-m_-8401468728650448730gmail-ms-rteTableOddRow-lightlines" style="height:15pt;border-collapse:collapse;border:1px solid transparent"><td height="20" class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines" style="height:15pt">0.125</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">--</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines">-2196.53 </td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines">-2273.29</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines"> -22497.9</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines"> -2203.83</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableEvenCol-lightlines"> -3215.92</td><td class="gmail-m_-8401468728650448730gmail-xl66 gmail-m_-8401468728650448730gmail-ms-rteTableOddCol-lightlines"> -2258.14​<br></td></tr></tbody></table><br style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">The input file of the scf calculation is shown below:</span><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">##############################<wbr>##########<br></div><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><div> &control</div><div>    calculation='scf'</div><div>    restart_mode='from_scratch',</div><div>    prefix='K3C60',</div><div>    pseudo_dir = './',</div><div>    outdir='./',</div><div>    tstress = .true.</div><div><span style="font-size:12pt">    tprnfor = .true.</span></div><div> /</div><div> &system</div><div>    ibrav= 2,<span style="font-size:12pt"> celldm(1)= 26.9097,</span><span style="font-size:12pt"> nat=63,</span><span style="font-size:12pt"> ntyp=2,</span><span style="font-size:12pt"> nbnd=<wbr>137</span></div><div>    ecutwfc = 70,<span style="font-size:12pt"> ecutrho = </span><span style="font-size:12pt">280</span></div><div>    occupations='smearing', smearing='gaussian', degauss=0.005</div><div> /</div><div> &electrons</div><div>    mixing_beta = 0.7,<span style="font-size:12pt"> conv_thr = 1.0D-10</span></div><div> /<br></div><div> &ions</div><div>    ion_dynamics = 'damp'<br></div><div> /</div><div>ATOMIC_SPECIES</div><div> C  12  C.pbe-mt.UPF</div><div> K  39.1  K.pbe-mt_norel.UPF</div><div>ATOMIC_POSITIONS (angstrom)</div><div>C        1.167584737   3.033367455   1.424268580</div><div>C        0.721014984   2.305670430   2.591830404</div><div>C       -0.721014984   2.305670430   2.591830404<br></div><div>.<br></div><div>.<br></div><div>.</div><div><div>K_POINTS automatic</div><div>4 4 4 1 1 1</div><div><span style="font-size:12pt">##############################<wbr>##########</span></div></div></div><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">With the phonon calculation input file:</div><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">##############################<wbr>##########</div><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px"><div>Phonon of K3C60</div><div> &inputph</div><div>  tr2_ph=1.0d-17,</div><div>  prefix='K3C60',</div><div>  recover=.true.</div><div>  amass(1)=12<br></div><div>  amass(2)=39.1</div><div>  outdir='./',</div><div>  fildyn='K3C60.dynG',</div><div> /</div><div>0.0 0.0 0.0<br></div></div><div style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:16px">##############################<wbr>##########<br><br><p style="margin-top:0px;margin-bottom:0px">Best regards<br></p><p style="margin-top:0px;margin-bottom:0px">Zhishuo Huang</p></div></div>