<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<style type="text/css" style="display:none;"><!-- P {margin-top:0;margin-bottom:0;} --></style>
<div id="divtagdefaultwrapper" style="font-size:12pt;color:#000000;font-family:Calibri,Helvetica,sans-serif;" dir="ltr">
<p>Dear Liang,</p>
<p><br>
</p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;">> It is very slow, it is normal?</span><br>
</p>
<p><br>
</p>
<p>Yes</p>
<p><br>
</p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;">> My system consists of 80 atoms...</span><br>
</p>
<p><br>
</p>
<p>For such a large system DFPT+U is expected to be very slow, in particular because the calculation of <span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont; font-size: 12pt;">d2ns_bare matrix (second "bare" derivative of the occupation
matrix ns) is computationally very expensive. I suggest to use the frozen-phonon approach (Phonopy).</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont; font-size: 12pt;"><br>
</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont; font-size: 12pt;">Greetings,</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont; font-size: 12pt;">Iurii</span></p>
<p><br>
</p>
<div id="Signature">
<div id="divtagdefaultwrapper" dir="ltr" style="font-size: 12pt; color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif, Helvetica, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols;">
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<font size="3" face="'Times New Roman', Times, serif" color="808080">--<br>
Dr. Iurii TIMROV<br>
Postdoctoral Researcher<br>
<font color="808080"><font face="'Times New Roman', Times, serif"></font></font></font></div>
<font color="808080"></font>
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<font size="3" face="'Times New Roman', Times, serif" color="808080">STI - IMX <font color="808080">
<font face="'Times New Roman', Times, serif">- THEOS</font></font></font><font size="3" face="'Times New Roman', Times, serif" color="808080"> and NCCR - MARVEL<br>
</font></div>
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<font size="3" face="'Times New Roman', Times, serif" color="808080"><font size="3" face="'Times New Roman', Times, serif" color="808080">Swiss Federal Institute of Technology Lausanne (EPFL<font color="808080"><font face="'Times New Roman', Times, serif">)</font></font></font><br>
</font></div>
<font color="808080"></font>
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<font size="3" face="'Times New Roman', Times, serif" color="808080">CH-1015 Lausanne, Switzerland<br>
+41 21 69 34 881</font></div>
<div name="divtagdefaultwrapper" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:; margin:0">
<a href="http://people.epfl.ch/265334" tabindex="0" id="LPNoLP">http://people.epfl.ch/265334</a><br>
</div>
</div>
</div>
</div>
</div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> users <users-bounces@lists.quantum-espresso.org> on behalf of LEUNG Clarence <liangxy123@hotmail.com><br>
<b>Sent:</b> Saturday, October 17, 2020 8:53:18 AM<br>
<b>To:</b> users@lists.quantum-espresso.org<br>
<b>Subject:</b> [QE-users] ph.x calculation with DPT+U</font>
<div> </div>
</div>
<div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Dear QEusers,</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Recently, I do ph.x calculation with DPT+U in QE6.6. However, it is very very slow. The output file running for four days as follows:</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Atomic wfc used for the projector on the Hubbard manifold are NOT orthogonalized
<div><br>
</div>
<div> Calculating the dnsbare matrix...</div>
<div><br>
</div>
<div> Calculating the dnsorth_cart matrix...</div>
<div><br>
</div>
<div> Alpha used in Ewald sum = 2.8000</div>
<div><br>
</div>
<div> Calculating the d2ns_bare matrix. It might take a while!</div>
<div> k point # 1 out of 2</div>
<br>
The specification of my server is two nodes with 64 cores (Xeon e5) and 512G RAMs. My system consists of 80 atoms, and the input files of ph.x si as follows:</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
&INPUTPH
<div> outdir='',</div>
<div> prefix='',</div>
<div> tr2_ph = 1d-12,</div>
<div> ldisp = .true. ,</div>
<div> fildyn ='' ,</div>
<div> epsil=.false.,</div>
<div> trans=.true.,</div>
<div> nq1 = 1 ,</div>
<div> nq2 = 1 ,</div>
<div> nq3 = 1 ,</div>
<div> nat_todo = 1,</div>
<div> alpha_mix(1) = 0.07,</div>
<div>/</div>
79<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
It is very slow, it is normal? It is very appreciated that give me some advices.</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Best regards,</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
LIANG</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Postdoc</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
City University of Hong Kong</div>
</div>
</body>
</html>