<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">I’m not an expert about el-ph calculations. However, if it were a calculation made by myself,<div class="">I would never trust Tc values obtained after modifying by hand lambda.f90, even if they were perfectly reasonable.</div><div class=""><br class=""></div><div class="">el-ph calculations for sure require extremely well converged electron calculations as well as well extremely well converged phonon</div><div class="">calculations. So I would go through the phonon calculation, understand why there are negative frequencies and,</div><div class="">even once you have obtained all positive frequencies, understand whether or not they are converged.</div><div class=""><br class=""></div><div class="">Giovanni<br class=""><div class=""><br class=""></div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On 28 Jul 2017, at 13:26, Isaiah Moses <<a href="mailto:imoses87@gmail.com" class="">imoses87@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class=""><div class=""><div class=""><div class=""><div class=""><div class=""><div class=""><div class=""><div class=""></div>Thanks a lot, Dr Giovanni.</div>I appreciate your response.<br class=""></div>We observed few values of frequencies to be negative.<br class=""></div>Matdyn1 has few more with others having either the first or the first 2/3 to be negative.<br class=""></div>We set those to be zero, modifying lambda.f90 code.<br class=""><br class=""></div>Could that be the problem?<br class=""><br class=""></div>I've attached the input/output for lambda.x execution. Also matdyn1.<br class=""><br class=""></div>There are 62-points and 33 irreps.<br class=""></div>I appreciate your time.<br clear="all" class=""><br class="">-- <br class=""><div class="gmail_signature"><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div dir="ltr" class=""><div class=""><div class=""><div class="">Isaiah Abu Moses<br class=""></div><div class="">Graduate Student,<br class=""></div>Physics Department,<br class=""></div>University of Ibadan,<br class=""></div>Nigeria<br class=""></div></div></div></div></div></div>
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<span id="cid:BA15F0F8-2C6A-497C-88EB-3E48A5D80301"><CyanoPh_lambda.in></span><span id="cid:672076C6-00A2-4A3F-8E54-485EA538F27D"><CyanoPh_lambda.out></span><span id="cid:0130F599-4B68-49C9-8638-9B78F799195C"><matdyn1></span>_______________________________________________<br class="">Pw_forum mailing list<br class=""><a href="mailto:Pw_forum@pwscf.org" class="">Pw_forum@pwscf.org</a><br class="">http://pwscf.org/mailman/listinfo/pw_forum</div></blockquote></div><br class=""><div class="">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">-- <br class=""><br class="">Giovanni Cantele, PhD<br class="">CNR-SPIN<br class="">c/o Dipartimento di Fisica<br class="">Universita' di Napoli "Federico II"<br class="">Complesso Universitario M. S. Angelo - Ed. 6<br class="">Via Cintia, I-80126, Napoli, Italy<br class="">e-mail: <a href="mailto:giovanni.cantele@spin.cnr.it" class="">giovanni.cantele@spin.cnr.it</a><br class="">Phone: +39 081 676910<br class="">Skype contact: giocan74<br class=""><br class="">ResearcherID: <a href="http://www.researcherid.com/rid/A-1951-2009" class="">http://www.researcherid.com/rid/A-1951-2009</a><br class="">Web page: <a href="http://people.fisica.unina.it/~cantele" class="">http://people.fisica.unina.it/~cantele</a><br class=""></div>
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