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<p>Dear Vivek,</p>
<p><br>
</p>
<p><font style="font-family: verdana, sans-serif, serif, "EmojiFont";" face="verdana,sans-serif">> I received an error message '<font style="font-family: Arial, Helvetica, sans-serif, serif, "EmojiFont";" face="Arial,Helvetica,sans-serif"> Error in routine
lr_readin (1):</font><font style="font-family: Arial, Helvetica, sans-serif, serif, "EmojiFont";" face="Arial,Helvetica,sans-serif"> Linear response calculation not implemented for PAW</font>' when I used the pseudos from SSSP for the turbo_lanczos.x method.</font><br>
</p>
<p><br>
</p>
<p>Yes, indeed, the TDDFPT codes of Quantum ESPRESSO currently support norm-conserving and ultrasoft pseudopotentials. PAW is not supported in TDDFPT.</p>
<p><br>
</p>
<p><font style="font-family: verdana, sans-serif, serif, "EmojiFont";" face="verdana,sans-serif">> The SSSP contain Ultrasoft pseudopotential information but it does not contain NC.</font><br>
</p>
<p><br>
</p>
<p>In the SSSP library there are also norm-conserving pseudos (e.g. SG15 in black, Pseudo Dojo in orange).
<br>
</p>
<p><br>
</p>
<p><font style="font-family: verdana, sans-serif, serif, "EmojiFont";" face="verdana,sans-serif">> We can do TDDFT absorption calculation only by using NC, isn't it?</font><br>
</p>
<p><br>
</p>
<p>Norm-conserving and ultrasoft.</p>
<p><br>
</p>
<p>So, in your case you need pseudos for Ti and O. According to SSSP, for Ti you have GBRV-1.4 (ultrasoft), and this is OK. For O, the recommended pseudo is from the PSlibrary 0.3.1 PAW - this is not OK in your case because PAW is not supported in TDDFPT. Therefore,
you can check the table for O:</p>
<p><a href="https://www.materialscloud.org/discover/sssp/plot/efficiency/O" class="OWAAutoLink" id="LPlnk4451" previewremoved="true">https://www.materialscloud.org/discover/sssp/plot/efficiency/O</a></p>
<p>According to this table you should choose the "best" ultrasoft pseudo for O. Please check the SSSP page in order to understand how to read this table, and please check this paper: G. Prandini, A. Marrazzo, I. E. Castelli, N. Mounet and N. Marzari,
<a href="https://www.nature.com/articles/s41524-018-0127-2" target="_blank">npj Computational Materials
<b>4</b>, 72</a> (2018). <br>
</p>
<p><br>
</p>
<p>Greetings,</p>
<p>Iurii<br>
</p>
<p><br>
</p>
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<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>
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<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>
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<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 Vivek Christhunathan <vivekppn@gmail.com><br>
<b>Sent:</b> Tuesday, February 18, 2020 3:33:02 PM<br>
<b>To:</b> Quantum ESPRESSO users Forum<br>
<b>Subject:</b> Re: [QE-users] Reg- Absorption spectrum using TDDFPT (turbo_davidson.x, turbo_lanczos.x and epsilon.x)</font>
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<div class="gmail_default" style="font-family:verdana,sans-serif">Dear Iurii,</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif;font-size:16px">> G. Onida, L. Reining, A. Rubio, "Electronic excitations: density-functional versus many-body Green's-function
approaches", Rev. > Mod. Phys. 74, 601 (2002).</span> <br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">Thanks a lot for providing the reference.</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">
<p style="color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif;font-size:16px">
> Check this page for pseudos:</p>
<p style="color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif;font-size:16px">
> <a href="https://www.materialscloud.org/discover/sssp/table/efficiency" id="gmail-m_1186008341547109867LPlnk452766" target="_blank">https://www.materialscloud.org/discover/sssp/table/efficiency</a></p>
I received an error message '<span style="font-family:Arial,Helvetica,sans-serif"> Error in routine lr_readin (1):</span><span style="font-family:Arial,Helvetica,sans-serif"> Linear response calculation not implemented for PAW</span>' when I used the pseudos
from SSSP for the turbo_lanczos.x method. The SSSP contain Ultrasoft pseudopotential information but it does not contain NC. We can do TDDFT absorption calculation only by using NC, isn't it? The input files are given below for your kind perusal.</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"># for scf calculation</div>
&control<br>
calculation = 'scf'<br>
restart_mode = 'from_scratch'<br>
prefix = 'TiO2'<br>
tstress = .true.<br>
tprnfor = .true.<br>
pseudo_dir = './'<br>
outdir = './outTiO2'<br>
wf_collect=.true.<br>
forc_conv_thr = 1d-4<br>
!disk_io = 'none'<br>
/<br>
<br>
&system<br>
ibrav = 0<br>
celldm(1) = 14.35<br>
nat = 24<br>
ntyp = 2<br>
ecutwfc = 60.0<br>
ecutrho = 600.0<br>
nbnd = 300<br>
/<br>
<br>
&electrons<br>
mixing_beta = 0.3,<br>
conv_thr = 1.0d-8<br>
/<br>
<br>
&IONS<br>
/<br>
<br>
&cell<br>
cell_factor = 3.0d0<br>
/<br>
<br>
ATOMIC_SPECIES<br>
Ti 47.867 Ti_pbe_v1.4.uspp.F.UPF<br>
O 16.00 O.pbe-n-kjpaw_psl.0.1.UPF<br>
<br>
CELL_PARAMETERS (alat)<br>
1.017721118 0.000000000 0.000000000<br>
0.000000000 0.508858021 0.000000000<br>
0.000000000 0.000000000 1.298939229<br>
<br>
ATOMIC_POSITIONS (crystal)<br>
Ti 0.000000000 0.000000000 -0.000000846<br>
Ti 0.500000000 0.000000000 -0.000000839<br>
Ti 0.250000013 0.500000000 0.499999157<br>
Ti 0.750000019 0.500000000 0.499999157<br>
Ti 0.000000000 0.500000000 0.250000852<br>
Ti 0.500000000 0.500000000 0.250000854<br>
Ti 0.250000017 0.000000000 0.750000839<br>
Ti 0.750000015 0.000000000 0.750000839<br>
O 0.000000000 0.000000000 0.206573803<br>
O 0.500000000 0.000000000 0.206573797<br>
O 0.250000018 0.500000000 0.706573779<br>
O 0.750000014 0.500000000 0.706573779<br>
O 0.000000000 0.500000000 0.456574040<br>
O 0.500000000 0.500000000 0.456574023<br>
O 0.250000013 0.000000000 0.956574018<br>
O 0.750000019 0.000000000 0.956574018<br>
O 0.250000006 0.000000000 0.543426210<br>
O 0.750000026 0.000000000 0.543426210<br>
O 0.000000000 0.500000000 0.043426209<br>
O 0.500000000 0.500000000 0.043426213<br>
O 0.250000013 0.500000000 0.293425986<br>
O 0.750000019 0.500000000 0.293425986<br>
O 0.000000000 0.000000000 0.793425968<br>
O 0.500000000 0.000000000 0.793425982<br>
K_POINTS gamma<br>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"># for turbo_lanczos.x</div>
<div><br>
</div>
&lr_input<br>
prefix ='TiO2'<br>
outdir ='./outTiO2'<br>
restart_step = 100,<br>
restart = .false.<br>
/<br>
&lr_control<br>
itermax = 500<br>
ipol = 4<br>
d0psi_rs = .true.<br>
/<br>
<div class="gmail_default" style="font-family:verdana,sans-serif"> <br>
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<div style="background-color:transparent;margin-top:0px;margin-bottom:0px"><font face="verdana, sans-serif"><span style="background-color:transparent;color:rgb(0,0,0)">Kind Regards,</span><br>
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<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek C</font></p>
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<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">__________________________________</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek Christhunathan</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">PhD researcher</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Mechanical Engineering</font></span></p>
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<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Feb 17, 2020 at 12:24 PM 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_6848758358673753443divtagdefaultwrapper" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif" dir="ltr">
<p>Dear Vivek,</p>
<p><br>
</p>
<p><font style="font-family:verdana,sans-serif,serif,EmojiFont" face="verdana,sans-serif">> Can you please provide any useful reference for the Bethe-Salpeter approach to <font style="font-family:Calibri,Helvetica,sans-serif,serif,EmojiFont" size="2" face="Calibri,Helvetica,sans-serif" color="black"><span style="font-size:16px">obtain
accurate absorption spectra for solids?</span></font></font><br>
</p>
<p><br>
</p>
<p>You can start from this reference:</p>
<p>G. Onida, L. Reining, A. Rubio, "Electronic excitations: density-functional versus many-body Green's-function approaches", Rev. Mod. Phys. 74, 601 (2002).</p>
<p><br>
</p>
<p>Greetings,</p>
<p>Iurii<br>
</p>
<p><br>
</p>
<div id="gmail-m_6848758358673753443Signature">
<div id="gmail-m_6848758358673753443divtagdefaultwrapper" 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_6848758358673753443LPNoLP" target="_blank">http://people.epfl.ch/265334</a><br>
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<div id="gmail-m_6848758358673753443divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" 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 Vivek Christhunathan <<a href="mailto:vivekppn@gmail.com" target="_blank">vivekppn@gmail.com</a>><br>
<b>Sent:</b> Monday, February 17, 2020 1:20:21 PM<br>
<b>To:</b> Quantum ESPRESSO users Forum<br>
<b>Subject:</b> Re: [QE-users] Reg- Absorption spectrum using TDDFPT (turbo_davidson.x, turbo_lanczos.x and epsilon.x)</font>
<div> </div>
</div>
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<div dir="ltr">
<div class="gmail_default" style="font-family:verdana,sans-serif">Dear Iurii,</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">Many thanks for your prompt reply and for your clear explanation about the related questions. </div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">I will try my calculation as per your technical comments and I will let you know here.</div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><br>
</div>
<div class="gmail_default" style="font-family:verdana,sans-serif">Can you please provide any useful reference for the Bethe-Salpeter approach to <span style="color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif;font-size:16px">obtain accurate absorption
spectra for solids?</span></div>
<div>
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<div style="background-color:transparent;margin-top:0px;margin-bottom:0px"><font face="verdana, sans-serif"><span style="background-color:transparent;color:rgb(0,0,0)">Kind Regards,</span><br>
</font></div>
<div style="background-color:transparent;margin-top:0px;margin-bottom:0px">
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek C</font></p>
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</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">__________________________________</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek Christhunathan</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">PhD researcher</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Mechanical Engineering</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">College of Engineering and Informatics</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Room 2053</font></span></p>
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<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif"><span lang="EN-US">National University of Ireland Galway</span><span lang="EN-US" style="color:rgb(51,102,255)"></span></font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Ireland</font></span></p>
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<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Fri, Feb 14, 2020 at 12:11 PM 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_6848758358673753443gmail-m_1226718586213944988divtagdefaultwrapper" style="font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif" dir="ltr">
<p>Dear Vivek,</p>
<p><br>
</p>
<p><span>In order to obtain accurate absorption spectra for solids, the Bethe-Salpeter approach is the right way to go. Nonetheless, please see my comments below.</span><br>
</p>
<p><br>
</p>
<p>epsilon.x is based on DFT and it is the code to compute absorption spectra in the independent-particle approximation, while turbo_lanczos.x and turbo_davidson.x are based on time-dependent DFT (TDDFT) and include interaction effects into account (it is possible
to disable interactions and obtain the same results as epsilon.x). Moreover, in epsilon.x the intensities are not fully correct, because there is a missing term in the commutator [V,r] (a contribution from the nonlocal part of the pseudo-potential is missing,
while in TDDFT codes above it is included). </p>
<p><br>
</p>
<p>Technical comments: you use a hybrid functional (<span>input_dft = 'pbe0'</span>), therefore you should use
<span>d0psi_rs = .true.</span> in <span>turbo_lanczos.x and turbo_davidson.x</span> in order to have the correct intensities in the absorption spectrum (this is true for molecules, while in solids it does not help).<br>
</p>
<p><br>
</p>
<p></p>
<div>> ATOMIC_SPECIES<br>
> Ti 47.867 Ti.upf<br>
> O 16.00 O.upf</div>
<p></p>
<p><br>
</p>
<p>Check this page for pseudos:</p>
<p><a href="https://www.materialscloud.org/discover/sssp/table/efficiency" id="gmail-m_6848758358673753443gmail-m_1226718586213944988LPlnk452766" target="_blank">https://www.materialscloud.org/discover/sssp/table/efficiency</a></p>
<p><br>
</p>
<p>Greetings,</p>
<p>Iurii<br>
</p>
<p><br>
</p>
<div id="gmail-m_6848758358673753443gmail-m_1226718586213944988Signature">
<div id="gmail-m_6848758358673753443gmail-m_1226718586213944988divtagdefaultwrapper" 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_6848758358673753443gmail-m_1226718586213944988LPNoLP" target="_blank">http://people.epfl.ch/265334</a><br>
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<div id="gmail-m_6848758358673753443gmail-m_1226718586213944988divRplyFwdMsg" dir="ltr">
<font face="Calibri, sans-serif" style="font-size:11pt" 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 Vivek Christhunathan <<a href="mailto:vivekppn@gmail.com" target="_blank">vivekppn@gmail.com</a>><br>
<b>Sent:</b> Friday, February 14, 2020 12:24:25 PM<br>
<b>To:</b> <a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a><br>
<b>Subject:</b> [QE-users] Reg- Absorption spectrum using TDDFPT (turbo_davidson.x, turbo_lanczos.x and epsilon.x)</font>
<div> </div>
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<div>
<div dir="ltr">
<div class="gmail_default"><span style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif">D</span><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif">ear QE users,</span><br>
</div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif"><br>
</span></div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif">Greetings!!!</span></div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif"><br>
</span></div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif">I am trying to find the absorption spectrum for the material 'TiO2' supercell (2*1*1) which consists of 24 atoms. I tried
a lot to find the absorption spectrum by reading all the related threads from QE. I have tried with all the methods such as turbo_davidson.x, turbo_lanczos.x and epsilon.x. I can only succeed with the use of epsilon.x but I am unable to get the same results
for the turbo_davidson.x and turbo_lanczos.x. I would like to know the reason behind this. And secondly to find an absorption spectrum of the material does epsilon.x method gives accurate results when compared with the other two? </span></div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif"><br>
</span></div>
<div class="gmail_default"><span class="gmail_default" style="background-color:transparent;color:rgb(0,0,0);font-family:verdana,sans-serif">Thirdly I have tried it for the Zn doped TiO2 supercell. This time all the methods did not give a hand for my calculation. </span><font face="verdana, sans-serif">The
input files are given below. I would be very grateful if you help me out in this regard.</font><br>
</div>
<div class="gmail_default"><font face="verdana, sans-serif"><br>
</font></div>
<div class="gmail_default"><font face="verdana, sans-serif">Please let me know if you need any further information. Looking forward to hearing from you.</font></div>
<div class="gmail_default"><font face="verdana, sans-serif"><br>
</font></div>
<div class="gmail_default"><font face="verdana, sans-serif">Thanks in advance. </font></div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default"><span style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">#</span><span style="color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">
self-consistent calculation</span> </div>
&control<br>
calculation = 'scf'<br>
prefix = 'TiO2'<br>
pseudo_dir = './'<br>
outdir = './outTiO2'<br>
!etot_conv_thr = 1e-5<br>
forc_conv_thr = 1e-4<br>
/<br>
&system<br>
ibrav = 0<br>
celldm(1) = 14.113<br>
nat = 24<br>
ntyp = 2<br>
ecutwfc = 80.0<br>
ecutrho = 800<br>
nbnd = 300<br>
input_dft = 'pbe0'<br>
/<br>
&electrons<br>
mixing_beta=0.3<br>
conv_thr = 1.0d-8<br>
diagonalization = 'david',<br>
mixing_mode = 'plain',<br>
/<br>
&IONS<br>
/<br>
&cell<br>
/<br>
CELL_PARAMETERS (alat)<br>
1.000927809 0.000000000 0.000000000<br>
0.000000000 0.500440909 0.000000000<br>
0.000000000 0.000000000 1.235414320<br>
ATOMIC_SPECIES<br>
Ti 47.867 Ti.upf<br>
O 16.00 O.upf<br>
ATOMIC_POSITIONS (<span class="gmail_default" style="font-family:verdana,sans-serif">crystal</span>)<br>
Ti 0.000000000 0.000000000 -0.000006420<br>
Ti 0.500000000 0.000000000 -0.000006418<br>
Ti 0.250000017 0.500000000 0.499993602<br>
Ti 0.750000015 0.500000000 0.499993602<br>
Ti 0.000000000 0.500000000 0.250006398<br>
Ti 0.500000000 0.500000000 0.250006394<br>
Ti 0.250000016 0.000000000 0.750006426<br>
Ti 0.750000016 0.000000000 0.750006426<br>
O 0.000000000 0.000000000 0.212511476<br>
O 0.500000000 0.000000000 0.212511476<br>
O 0.250000011 0.500000000 0.712511501<br>
O 0.750000021 0.500000000 0.712511501<br>
O 0.000000000 0.500000000 0.462514694<br>
O 0.500000000 0.500000000 0.462514705<br>
O 0.250000019 0.000000000 0.962514709<br>
O 0.750000013 0.000000000 0.962514709<br>
O 0.250000008 0.000000000 0.537488518<br>
O 0.750000024 0.000000000 0.537488518<br>
O 0.000000000 0.500000000 0.037488489<br>
O 0.500000000 0.500000000 0.037488487<br>
O 0.250000019 0.500000000 0.287485309<br>
O 0.750000013 0.500000000 0.287485309<br>
O 0.000000000 0.000000000 0.787485317<br>
O 0.500000000 0.000000000 0.787485307<br>
K_POINTS gamma<br>
<br>
<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">#</span><span style="color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">
turbo_lanczos.x calculation</span><span style="font-family:Arial,Helvetica,sans-serif"> </span></div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif"> </span><span style="font-family:Arial,Helvetica,sans-serif">&lr_input</span></div>
prefix ='TiO2'<br>
outdir ='./outTiO2'<br>
!restart_step = 100,<br>
!restart = .true.<br>
/<br>
&lr_control<br>
itermax = 500<br>
ipol = 1<br>
!d0psi_rs = .true.<br>
/
<div>
<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif"></span><span style="font-family:Arial,Helvetica,sans-serif"></span><span style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">#</span><span style="color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">
turbo_spectrum.x calculation</span><span style="font-family:Arial,Helvetica,sans-serif"> </span><span style="font-family:Arial,Helvetica,sans-serif"><br>
</span>&LR_INPUT<br>
prefix = 'TiO2'<br>
outdir = './outTiO2'<br>
itermax0 = 500<br>
itermax = 10000<br>
extrapolation = 'osc'<br>
epsil = 0.01<br>
units = 1<br>
start = 0.0<br>
end = 4.0<br>
increment = 0.01<br>
ipol = 1<br>
/<br>
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<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif"></span><span style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">#</span><span style="color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">
turbo_davidson.x calculation</span><span style="font-family:Arial,Helvetica,sans-serif"> </span></div>
<div class="gmail_default" style="font-family:verdana,sans-serif">&lr_input<br>
prefix = 'TiO2'<br>
outdir = './outTiO2'<br>
/<br>
&lr_dav<br>
!if_dft_spectrum = .false.<br>
num_eign = 5<br>
num_init = 10<br>
num_basis_max = 90<br>
residue_conv_thr = 1.0E-4<br>
start = 0.0 <br>
finish = 3.50<br>
step = 0.001<br>
broadening = 0.004<br>
reference = 0.3<br>
/<br>
<span style="font-family:Arial,Helvetica,sans-serif"></span><span style="font-family:Arial,Helvetica,sans-serif"></span><span style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">#</span><span style="color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre-wrap">
turbo_spectrum.x calculation</span> </div>
<span class="gmail_default" style="font-family:verdana,sans-serif"></span>&lr_input<br>
prefix = 'TiO2'<br>
outdir = './outTiO2'<br>
td = 'davidson'<br>
epsil = 0.004<br>
start = 0.0d0 <br>
end = 3.5d0<br>
increment = 0.001d0<br>
eign_file = 'TiO2.eigen'<br>
<div class="gmail_default" style="font-family:verdana,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif">/</span></div>
<div class="gmail_default" style="font-family:verdana,sans-serif"> <br>
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<div style="background-color:transparent;margin-top:0px;margin-bottom:0px"><font face="verdana, sans-serif"><span style="background-color:transparent;color:rgb(0,0,0)"><span class="gmail_default" style="font-family:verdana,sans-serif"></span>Kind Regards,</span><br>
</font></div>
<div style="background-color:transparent;margin-top:0px;margin-bottom:0px">
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek C</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif"><br>
</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">__________________________________</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif">Vivek Christhunathan</font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">PhD researcher</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Mechanical Engineering</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">College of Engineering and Informatics</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Room 2053</font></span></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif"><span lang="EN-US">Alice Perry Engineering Building</span><span lang="EN-US" style="color:rgb(51,102,255)"></span></font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><font face="verdana, sans-serif"><span lang="EN-US">National University of Ireland Galway</span><span lang="EN-US" style="color:rgb(51,102,255)"></span></font></p>
<p class="MsoNormal" align="left" style="color:rgb(0,0,0)"><span lang="EN-US"><font face="verdana, sans-serif">Ireland</font></span></p>
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v.christhunathan1@nuigalway.ie</a></font></div>
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