<html><head><meta content="text/html; charset=us-ascii" http-equiv="Content-Type"></head><body><div><div style="font-family: Calibri,sans-serif; font-size: 11pt;">Thanks a lot to Prof. Matteo Cococcioni and Pang Rui for your tips!<br></div></div><hr><span style="font-family: Tahoma,sans-serif; font-size: 10pt; font-weight: bold;">Da: </span><span style="font-family: Tahoma,sans-serif; font-size: 10pt;">pw_forum-request@pwscf.org</span><br><span style="font-family: Tahoma,sans-serif; font-size: 10pt; font-weight: bold;">Inviato: </span><span style="font-family: Tahoma,sans-serif; font-size: 10pt;">16/05/2014 12:03</span><br><span style="font-family: Tahoma,sans-serif; font-size: 10pt; font-weight: bold;">A: </span><span style="font-family: Tahoma,sans-serif; font-size: 10pt;">pw_forum@pwscf.org</span><br><span style="font-family: Tahoma,sans-serif; font-size: 10pt; font-weight: bold;">Oggetto: </span><span style="font-family: Tahoma,sans-serif; font-size: 10pt;">Pw_forum Digest, Vol 82, Issue 16</span><br><br>Send Pw_forum mailing list submissions to<br> pw_forum@pwscf.org<br><br>To subscribe or unsubscribe via the World Wide Web, visit<br> http://pwscf.org/mailman/listinfo/pw_forum<br>or, via email, send a message with subject or body 'help' to<br> pw_forum-request@pwscf.org<br><br>You can reach the person managing the list at<br> pw_forum-owner@pwscf.org<br><br>When replying, please edit your Subject line so it is more specific<br>than "Re: Contents of Pw_forum digest..."<br><br><br>Today's Topics:<br><br> 1. Hubbard coefficients (Tommy)<br> 2. Re: Hubbard coefficients (Matteo Cococcioni)<br> 3. drawing the HOMO and LUMO (Banafshe Noori)<br> 4. Hubbard U (Tommaso Francese)<br> 5. Re: Hubbard U (Matteo Cococcioni)<br> 6. Re: Hubbard U (Pang Rui)<br><br><br>----------------------------------------------------------------------<br><br>Message: 1<br>Date: Thu, 15 May 2014 23:16:48 +0200<br>From: Tommy <neutrinofrancese@gmail.com><br>Subject: [Pw_forum] Hubbard coefficients<br>To: "pw_forum@pwscf.org" <pw_forum@pwscf.org><br>Message-ID: <53752edb.81430f0a.46b0.0c2a@mx.google.com><br>Content-Type: text/plain; charset="windows-1252"<br><br>Thanks to both Giuseppe Mattioli and Pang Gui for their help!!! <br>However, I need to ask one more question about the process for obtaining Hubbard coefficients: I follow the tutorials posted with the links, but a thing wasn't clear to me. After scf simple calculation, I need to "perturb" the system in a range between -0.1 & 0.1 eV. But: do i need to save a file for every perturbation induced to the system?<br>How can i set to QE to take every previous result and compute the U term?<br>Be patient, but I'm alone and i trying to do the best for my thesis!!!<br>Best regards,<br>Tommaso.<br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: http://pwscf.org/pipermail/pw_forum/attachments/20140515/401b5086/attachment-0001.html <br><br>------------------------------<br><br>Message: 2<br>Date: Fri, 16 May 2014 00:06:39 +0200<br>From: Matteo Cococcioni <matteo@umn.edu><br>Subject: Re: [Pw_forum] Hubbard coefficients<br>To: PWSCF Forum <pw_forum@pwscf.org><br>Message-ID:<br> <CAMZASgEDkxq6rpEGcazeVFmy_WO1iXAsPbW589DpaVYaMRgUeg@mail.gmail.com><br>Content-Type: text/plain; charset="utf-8"<br><br>Hi Tommaso,<br><br>for every perturbation the run should restart from the potential (and<br>wavefunctions) of the uperturbed run. So you need to save the scratch<br>directory of the latter and copy it to the one used by the perturbed run<br>before each calculation. This should be evident from the tutorial files.<br>Also make sure that diago_thr_init (the threshold for the diagonalization<br>of the Hamiltonian at each step) is set equal to the value it had at the<br>last iteration of the unperturbed run, so that the diagonalization at the<br>first iteration of the perturbed run is equally ccurate. Hope this is not<br>confusing.<br><br>best,<br><br>Matteo<br><br><br><br><br>On Thu, May 15, 2014 at 11:16 PM, Tommy <neutrinofrancese@gmail.com> wrote:<br><br>> Thanks to both Giuseppe Mattioli and Pang Gui for their help!!!<br>> However, I need to ask one more question about the process for obtaining<br>> Hubbard coefficients: I follow the tutorials posted with the links, but a<br>> thing wasn't clear to me. After scf simple calculation, I need to "perturb"<br>> the system in a range between -0.1 & 0.1 eV. But: do i need to save a file<br>> for every perturbation induced to the system?<br>> How can i set to QE to take every previous result and compute the U term?<br>> Be patient, but I'm alone and i trying to do the best for my thesis!!!<br>> Best regards,<br>> Tommaso.<br>><br>> _______________________________________________<br>> Pw_forum mailing list<br>> Pw_forum@pwscf.org<br>> http://pwscf.org/mailman/listinfo/pw_forum<br>><br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: http://pwscf.org/pipermail/pw_forum/attachments/20140516/ddbcb0ae/attachment-0001.html <br><br>------------------------------<br><br>Message: 3<br>Date: Fri, 16 May 2014 07:43:04 +0100 (BST)<br>From: Banafshe Noori <b_noori88@yahoo.com><br>Subject: [Pw_forum] drawing the HOMO and LUMO<br>To: "pw_forum@pwscf.org" <pw_forum@pwscf.org><br>Message-ID:<br> <1400222584.49542.YahooMailNeo@web171505.mail.ir2.yahoo.com><br>Content-Type: text/plain; charset="iso-8859-1"<br><br>Dear all,<br><br><br>Hi<br><br><br>How can? draw? the HOMO and LUMO orbital of nanotube? with pwscf package?<br><br>please guide me.<br><br>thanks.<br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: http://pwscf.org/pipermail/pw_forum/attachments/20140516/08df6ff0/attachment-0001.html <br><br>------------------------------<br><br>Message: 4<br>Date: Fri, 16 May 2014 10:40:54 +0200<br>From: Tommaso Francese <neutrinofrancese@gmail.com><br>Subject: [Pw_forum] Hubbard U<br>To: pw_forum@pwscf.org<br>Message-ID: <D2267729-B244-4A28-B36F-07740EED2067@gmail.com><br>Content-Type: text/plain; charset=windows-1252<br><br>Dear all,<br> as you suggested, i try to follow your tutorial for the Hubbard U coefficients determination, but i have some practical difficulties. <br><br>Summarizing, i proceded as follow:<br><br>step 1)?> i have done a simple SCF with very low coefficients for Hubbard_U1 and Hubbard_U2, enabling the wavefunction separate collection (wf_collect) ;<br>step 2)?> i have performed some SCF, restarting from the charge file stored previously, introducing some fluctuation values in Hubbard_alpha (?), is it correct? <br><br>the problem is at this point: do i need to rename every scf-file in which i performed a different perturbation? How can i, in the next step, ?recall? the different perturbation that i performed previously? <br><br>At this point is obvious that i don?t know also how to calculate the response functions and so, obtaining the Hubbard U coefficient.<br><br>Can someone help me? <br>Thanks a lot,<br>Tommaso,<br>Universit? C? Foscari of Venice<br><br><br>------------------------------<br><br>Message: 5<br>Date: Fri, 16 May 2014 11:08:22 +0200<br>From: Matteo Cococcioni <matteo@umn.edu><br>Subject: Re: [Pw_forum] Hubbard U<br>To: PWSCF Forum <pw_forum@pwscf.org><br>Message-ID:<br> <CAMZASgEWM9Gn0bWrgyMc5ZOb3RvSJK2EtDsfD3ePPBCA4p2nAQ@mail.gmail.com><br>Content-Type: text/plain; charset="utf-8"<br><br>Dear Tommaso,<br><br>see below.<br><br>On Fri, May 16, 2014 at 10:40 AM, Tommaso Francese <<br>neutrinofrancese@gmail.com> wrote:<br><br>> Dear all,<br>> as you suggested, i try to follow your tutorial for the Hubbard U<br>> coefficients determination, but i have some practical difficulties.<br>><br>> Summarizing, i proceded as follow:<br>><br>> step 1)?> i have done a simple SCF with very low coefficients for<br>> Hubbard_U1 and Hubbard_U2, enabling the wavefunction separate collection<br>> (wf_collect) ;<br>><br><br>I don't think wf_collect is necessary. should not be harmful either<br><br><br>> step 2)?> i have performed some SCF, restarting from the charge file<br>> stored previously, introducing some fluctuation values in Hubbard_alpha<br>> (?), is it correct?<br>><br>><br>right.<br><br><br>> the problem is at this point: do i need to rename every scf-file in which<br>> i performed a different perturbation?<br><br><br><br>yes, otherwise you overwrite them each time. or you can redirect them to<br>different (properly named) directories.<br><br><br><br>> How can i, in the next step, ?recall? the different perturbation that i<br>> performed previously?<br>><br>><br>what do you exactly mean by "recall"? do you have difficulties in<br>recognizing outputs corresponding to different alphas? then see the naming<br>problem at the previous point.<br><br><br>> At this point is obvious that i don?t know also how to calculate the<br>> response functions and so, obtaining the Hubbard U coefficient.<br>><br>><br>this is what the tutorial is for. were you able to follow the instructions<br>to the end? Besides the one from the Santa Barbar school there is also<br>another one from a nother school in 2012 at Penn State. Maybe that is<br>better?<br><br>best,<br><br>Matteo<br><br><br><br><br>> Can someone help me?<br>> Thanks a lot,<br>> Tommaso,<br>> Universit? C? Foscari of Venice<br>> _______________________________________________<br>> Pw_forum mailing list<br>> Pw_forum@pwscf.org<br>> http://pwscf.org/mailman/listinfo/pw_forum<br>><br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: http://pwscf.org/pipermail/pw_forum/attachments/20140516/062301cb/attachment-0001.html <br><br>------------------------------<br><br>Message: 6<br>Date: Fri, 16 May 2014 18:00:01 +0800<br>From: Pang Rui <pang.r@sustc.edu.cn><br>Subject: Re: [Pw_forum] Hubbard U<br>To: PWSCF Forum <pw_forum@pwscf.org><br>Message-ID: <808f3429f31a41da6936fe47b999f2c5@127.0.0.1><br>Content-Type: text/plain; charset=UTF-8<br><br>Dear Tommaso:<br>I think maybe there are some misuderstanding. The following is what I do. <br>1:calculate a scf and save all the output(the key is the *.save folder in<br>fact)<br>2:Bulid several folders, for example, 10.<br>3:Copy the scf file into the 10 folders<br>4:Put the perturbative input files which have different hubbard alpha into<br>the 10 folders and do the calculation. Of course, some additional input<br>must be added as Mr.Cococcioni suggested in the other mail of you. <br>5:Grep "Tr" in every output files. The second one is the n0, the last one<br>is the n.Record the data of the one you take perturbation<br>6:Fitting two lines of n and n0(x) vs hubbard_alpha(y), the difference of<br>the slopes is the Hubbard U.<br>This is the process of calculating single U in a cell.<br>Hope this can help you.<br>On Fri, 16 May 2014 10:40:54 +0200, Tommaso Francese<br><neutrinofrancese@gmail.com> wrote:<br>> Dear all,<br>> as you suggested, i try to follow your tutorial for the Hubbard U<br>> coefficients determination, but i have some practical difficulties.<br>> <br>> Summarizing, i proceded as follow:<br>> <br>> step 1)?> i have done a simple SCF with very low coefficients for<br>> Hubbard_U1 and Hubbard_U2, enabling the wavefunction separate collection<br>> (wf_collect) ;<br>> step 2)?> i have performed some SCF, restarting from the charge file<br>> stored previously, introducing some fluctuation values in Hubbard_alpha<br>> (?), is it correct? <br>> <br>> the problem is at this point: do i need to rename every scf-file in<br>which<br>> i performed a different perturbation? How can i, in the next step,<br>?recall?<br>> the different perturbation that i performed previously? <br>> <br>> At this point is obvious that i don?t know also how to calculate the<br>> response functions and so, obtaining the Hubbard U coefficient.<br>> <br>> Can someone help me? <br>> Thanks a lot,<br>> Tommaso,<br>> Universit? C? Foscari of Venice<br>> _______________________________________________<br>> Pw_forum mailing list<br>> Pw_forum@pwscf.org<br>> http://pwscf.org/mailman/listinfo/pw_forum<br><br><br>------------------------------<br><br>_______________________________________________<br>Pw_forum mailing list<br>Pw_forum@pwscf.org<br>http://pwscf.org/mailman/listinfo/pw_forum<br><br>End of Pw_forum Digest, Vol 82, Issue 16<br>****************************************<br></body></html>