<div dir="ltr"><div class="gmail_default" style="font-size:large">Thanks, Iurii. Yes, the spectrum with gamma point is quite reasonable but do not match with the experimental observation. It could be some other issue. <br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">However, I am wondering how to do the TDDFT calculation for a doped/defected structure with extra electron or hole. I tried to use turbo_davidson starting from i) scf calculation with npsin= 2 and total magnetization and turbo_davidson does not work since I believe it does not</div><div class="gmail_default" style="font-size:large">for spin-polarized system, then, I tried ii) scf calculation without any spin-polarization and the scf calculation did not run since it cannot work with an extra charge and 'fixed' occupation, and, finally, iii) scf with smearing but turbo_davidson does not support scf calculation with smearing (ref: <a href="https://lists.quantum-espresso.org/pipermail/users/2017-January/037363.html">https://lists.quantum-espresso.org/pipermail/users/2017-January/037363.html</a>) <br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">I believe in this case I cannot use TDDFT of QE to calculate absorption spectra of a defected or doped structure. Am I right here?</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Best,</div><div class="gmail_default" style="font-size:large">Abhirup<br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br clear="all"></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><font face="arial, sans-serif" color="#0b5394">-------------------------------------------------------------------------------------------------------------------------------------</font><div><font face="arial, sans-serif" color="#0b5394">Abhirup Patra</font></div><div><font face="arial, sans-serif" color="#0b5394">Postdoctoral Research Fellow</font></div><div><font face="arial, sans-serif" color="#0b5394">Department of Chemistry</font></div><div><font face="arial, sans-serif" color="#0b5394">University of Pennsylvania</font></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Dec 18, 2019 at 4:00 AM Timrov Iurii <<a href="mailto:iurii.timrov@epfl.ch">iurii.timrov@epfl.ch</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<div id="gmail-m_-5166616141411196292divtagdefaultwrapper" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif" dir="ltr">
<p>Dear Abhirup,</p>
<p><br>
</p>
<p><font size="4">> However, I am not sure with the number of atoms (~120 or more) GW-BSE calculations with supercell is actually feasible.
</font><br>
</p>
<p><br>
</p>
<p>Yes, I understand the issue. I do not know if it is feasible. You may try to use e.g. Yambo and see how it goes. Otherwise, since you have already quite a big cell, maybe with k=0 you obtain quite a reasonably converged spectrum (to be checked w.r.t. the
cell size) at the TDDFT level in the adiabatic approximation.</p>
<p><br>
</p>
<p>Regards,</p>
<p>Iurii<br>
</p>
<p><br>
</p>
<div id="gmail-m_-5166616141411196292Signature">
<div id="gmail-m_-5166616141411196292divtagdefaultwrapper" dir="ltr" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif,"EmojiFont","Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols">
<div name="divtagdefaultwrapper">
<div name="divtagdefaultwrapper">
<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">
<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">
<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">
<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">
<a href="http://people.epfl.ch/265334" id="gmail-m_-5166616141411196292LPNoLP" target="_blank">http://people.epfl.ch/265334</a><br>
</div>
</div>
</div>
</div>
</div>
<hr style="display:inline-block;width:98%">
<div id="gmail-m_-5166616141411196292divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> users <<a href="mailto:users-bounces@lists.quantum-espresso.org" target="_blank">users-bounces@lists.quantum-espresso.org</a>> on behalf of Abhirup Patra <<a href="mailto:abhirupp@sas.upenn.edu" target="_blank">abhirupp@sas.upenn.edu</a>><br>
<b>Sent:</b> Tuesday, December 17, 2019 4:47:01 PM<br>
<b>To:</b> Quantum ESPRESSO users Forum<br>
<b>Subject:</b> Re: [QE-users] k-point algorithm is not tested yet turbo davidson</font>
<div> </div>
</div>
<div>
<div dir="ltr">
<div class="gmail_default" style="font-size:large">Thanks very much, Iurii. I really appreciate your answer and it does make sense to me. With gamma point only it works fine. And, you are right, my system is a solid and I am
<br>
</div>
<div class="gmail_default" style="font-size:large">trying to simulate the optical spectrum. However, I am not sure with the number of atoms (~120 or more) GW-BSE calculations with supercell is actually feasible.
<br>
</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">Best,</div>
<div class="gmail_default" style="font-size:large">Abhirup<br>
</div>
<div>
<div dir="ltr">
<div dir="ltr"><font face="arial, sans-serif" color="#0b5394">-------------------------------------------------------------------------------------------------------------------------------------</font>
<div><font face="arial, sans-serif" color="#0b5394">Abhirup Patra</font></div>
<div><font face="arial, sans-serif" color="#0b5394">Postdoctoral Research Fellow</font></div>
<div><font face="arial, sans-serif" color="#0b5394">Department of Chemistry</font></div>
<div><font face="arial, sans-serif" color="#0b5394">University of Pennsylvania</font></div>
</div>
</div>
</div>
<br>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Tue, Dec 17, 2019 at 7:50 AM Timrov Iurii <<a href="mailto:iurii.timrov@epfl.ch" target="_blank">iurii.timrov@epfl.ch</a>> wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<div id="gmail-m_-5166616141411196292gmail-m_-625169129654915766divtagdefaultwrapper" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif" dir="ltr">
<p>Dear Abhirup,</p>
<p><br>
</p>
<p>As you can see from the error message of the turbo_davidson code, the k-points algorithm is not supported. Only Gamma point sampling can be used.</p>
<p><br>
</p>
<p>If I understand correctly, your system is a solid, right? And you want to use a unit cell with a k-points mesh, right? The turbo_davidson cannot be used in this case. You may try to use a supercell with a Gamma point sampling. But be careful when using TDDFT
in the adiabatic approximation for the absorption spectroscopy of solids. I recommend that you check literature on this topic. Maybe you will need to resort to the BSE approach.</p>
<p><br>
</p>
<p>HTH</p>
<p><br>
</p>
<p>Iurii Timrov<br>
</p>
<p><br>
</p>
<div id="gmail-m_-5166616141411196292gmail-m_-625169129654915766Signature">
<div id="gmail-m_-5166616141411196292gmail-m_-625169129654915766divtagdefaultwrapper" dir="ltr" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif,"EmojiFont","Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols">
<div name="divtagdefaultwrapper">
<div name="divtagdefaultwrapper"><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"><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"><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"><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"><a href="http://people.epfl.ch/265334" id="gmail-m_-5166616141411196292gmail-m_-625169129654915766LPNoLP" target="_blank">http://people.epfl.ch/265334</a><br>
</div>
</div>
</div>
</div>
</div>
<hr style="display:inline-block;width:98%">
<div id="gmail-m_-5166616141411196292gmail-m_-625169129654915766divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> users <<a href="mailto:users-bounces@lists.quantum-espresso.org" target="_blank">users-bounces@lists.quantum-espresso.org</a>>
on behalf of Abhirup Patra <<a href="mailto:abhirupp@sas.upenn.edu" target="_blank">abhirupp@sas.upenn.edu</a>><br>
<b>Sent:</b> Monday, December 16, 2019 6:12:08 PM<br>
<b>To:</b> Quantum ESPRESSO users Forum<br>
<b>Subject:</b> [QE-users] k-point algorithm is not tested yet turbo davidson</font>
<div> </div>
</div>
<div>
<div dir="ltr">
<div class="gmail_default" style="font-size:large">Hello, <br>
</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">I am trying to use turbo_davidson starting from a SCF calculation using PBE without smearing and spin-polarization. This system is a non-metal with bandgap of 2.6 eV. I gave uniform k-mesh as follows for the
bcc structure with lattice constant of 10.34 angstrom. <br>
</div>
<br>
K_POINTS {crystal_b}<br>
9<br>
0.0 0.0 0.0 0<br>
0.0 -0.5 0.0 0<br>
0.0 -0.5 0.5 0<br>
0.5 -0.5 0.5 0<br>
0.5 -0.5 0.0 0<br>
0.5 0.0 0.0 0<br>
0.0 0.0 0.0 0<br>
0.0 0.0 0.5 0<br>
0.5 0.0 0.5 0
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">&lr_input<br>
prefix = 'pristine_pbe'<br>
outdir = './'<br>
! wfcdir = './'<br>
/<br>
&lr_dav<br>
num_eign = 35,<br>
num_init = 70,<br>
num_basis_max = 200,<br>
start = 0.0d0<br>
finish = 3.5d0<br>
step = 0.001d0<br>
broadening = 0.005d0<br>
/</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">However, I am getting the following error:</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large"> Error in routine lr_readin (1):<br>
k-point algorithm is not tested yet</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">I am wondering if there is a simple way out to this problem other than explicitly testing different k mesh combinations.
<br>
</div>
<div class="gmail_default" style="font-size:large"><br>
</div>
<div class="gmail_default" style="font-size:large">Best,</div>
<div class="gmail_default" style="font-size:large">Abhirup<br clear="all">
</div>
<div>
<div dir="ltr">
<div dir="ltr"><font face="arial, sans-serif" color="#0b5394">-------------------------------------------------------------------------------------------------------------------------------------</font>
<div><font face="arial, sans-serif" color="#0b5394">Abhirup Patra</font></div>
<div><font face="arial, sans-serif" color="#0b5394">Postdoctoral Research Fellow</font></div>
<div><font face="arial, sans-serif" color="#0b5394">Department of Chemistry</font></div>
<div><font face="arial, sans-serif" color="#0b5394">University of Pennsylvania</font></div>
</div>
</div>
</div>
</div>
</div>
</div>
_______________________________________________<br>
Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu/quantum-espresso" rel="noreferrer" target="_blank">www.max-centre.eu/quantum-espresso</a>)<br>
users mailing list <a href="mailto:users@lists.quantum-espresso.org" target="_blank">
users@lists.quantum-espresso.org</a><br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote>
</div>
</div>
</div>
_______________________________________________<br>
Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu/quantum-espresso" rel="noreferrer" target="_blank">www.max-centre.eu/quantum-espresso</a>)<br>
users mailing list <a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a><br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote></div>