<DIV>Dear Sanjeev,</DIV> <DIV>I would like to say you may find example 5 useful for your questions about k points.</DIV> <DIV>There you can find how to enter k points manually for scf and nscf calculations.<BR>I think it is necessary to check the weight of k points for scf,</DIV> <DIV>but for nscf band structure calc. as in example 05 that may not have any significance,</DIV> <DIV> </DIV> <DIV>For the elastic constants,</DIV> <DIV>using the well known strain-stress relation</DIV> <DIV>and elastic energy density expression, is the first way that comes to my mind.</DIV> <DIV>The convention about which strain to use to obtain which elastic constant,</DIV> <DIV>is probably told in many references that one can check in the literature. </DIV> <DIV>For a simple explanation for a simple system,</DIV> <DIV>you can take a look at</DIV> <DIV>Phys. Rev. B 60, 791 - 799 (1999) and erratum.<BR></DIV> <DIV>I am a new user of QE, and not
even a grad student yet,</DIV> <DIV>so if I said sth wrong, I hope more experienced users will correct me.</DIV> <DIV> </DIV> <DIV>Bests,</DIV> <DIV>Emine Kucukbenli<BR></DIV> <DIV><B><I></I></B> </DIV> <DIV><B><I>Sanjeev Kumar Gupta <sanjeev0302@rediffmail.com></I></B> wrote:</DIV> <BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid"> <DIV>Thanking you Amin,<BR><BR>>>This is done in espresso code automatically for scf and nscf but for plotting band structure you should do it manually>><BR><BR>But what will be the maximum and minimum range of the k-point for band calculation and also you said in earlier suggestion that, for scf and nscf it is automatic,but we want to do manually the how we will proceeds?<BR><BR>>>I thought it is possible.negative or positive Fermi energy doesn't have physical meaning>><BR><BR>sorry, for again same question, what is significance of
negative fermi energy is any relation in other calculation.<BR><BR>I want to find out the elastic constant for my system, how we will proceeds?<BR><BR><BR>Regards<BR>sanjeev<BR><BR><BR>On Sun, 10 Dec 2006 Amin Babazadeh wrote :<BR>>Dear sanjeev<BR>><BR>><BR>><BR>>On 9 Dec 2006 04:44:31 -0000, Sanjeev Kumar Gupta <<BR>>sanjeev0302@rediffmail.com> wrote:<BR>>><BR>>>Respected sir,<BR>>><BR>>>i am sanjeev gupta, from india, working DFT calculation via<BR>>>Quantum-Espresso-3.1.1. I have doubts with k-ponits,<BR>>>1)How we choose k-points for diiferent system?<BR>>><BR>><BR>>dis is done in espresso code automatically for scf and nscf but for plotting<BR>>band structure you should do it manually<BR>><BR>>2)Is possible fermi energy negative for noble nitrides?<BR>>><BR>>.<BR>><BR>><BR>>3)Is neccessary same k-points for scf and nscf cycle or phX,phL and phG.?<BR>>>no you can
change it.for scf and nscf.usually the kpoint for scf<BR>>>calculation is smaller than nscf.about phX,phL and phG i don't have any<BR>>>idea.<BR>>><BR>><BR>>good luck<BR>>amin<BR>><BR>>with regards<BR>>>sanjeev gupta<BR>>><BR>>>====================================================<BR>>>Sanjeev Kumar Gupta<BR>>>Junior Research Fellow (DAE-BRNS)<BR>>>Computational Condensed Matter Physics Lab.(CCMP)<BR>>>Department of Physics, Faculty of Science,<BR>>>The M.S.University of Baroda, Vadodara - 390 002.<BR>>>Ph.No: +91-265-279 5339 (O) extn: 30-25<BR>>>mobile:09374616019<BR>>>Email: sanjeev0302@rediffmail.com<BR>>> sanjeev0302@yahoo.co.in<BR>>> skgupta-phy@msubaroda.ac.in<BR>>>====================================================<BR>>><BR>>>Residential Address-<BR>>><BR>>>Dr. Vikram Sarabhai
Hall,<BR>>>Room No.-95, Boys' Hostel,M.S.University Campus,<BR>>>Pratapgunj,Vadodara-390 002,Gujarat,INDIA<BR>>><BR>>><BR>>><BR>>><http://adworks.rediff.com/cgi-bin/AdWorks/sigclick.cgi/www.rediff.com/signature-home.htm/1507191490@Middle5?PARTNER=3><BR>><BR>><BR>><BR>><BR>>-- AMIN<BR></DIV>==================================================== <BR>Sanjeev Kumar Gupta <BR>Junior Research Fellow (DAE-BRNS) <BR>Computational Condensed Matter Physics Lab.(CCMP) <BR>Department of Physics, Faculty of Science, <BR>The M.S.University of Baroda, Vadodara - 390 002. <BR>Ph.No: +91-265-279 5339 (O) extn: 30-25 <BR>mobile:09374616019 <BR>Email: sanjeev0302@rediffmail.com <BR> sanjeev0302@yahoo.co.in <BR> skgupta-phy@msubaroda.ac.in <BR>==================================================== <BR><BR>Residential Address-
<BR><BR>Dr. Vikram Sarabhai Hall, <BR>Room No.-95, Boys' Hostel,M.S.University Campus, <BR>Pratapgunj,Vadodara-390 002,Gujarat,INDIA <BR><BR><BR><A href="http://adworks.rediff.com/cgi-bin/AdWorks/sigclick.cgi/www.rediff.com/signature-home.htm/1507191490@Middle5?PARTNER=3"><IMG hspace=0 src="http://adworks.rediff.com/cgi-bin/AdWorks/sigimpress.cgi/www.rediff.com/signature-home.htm/1963059423@Middle5?OAS_query=null&PARTNER=3" border=0></A> </BLOCKQUOTE><BR><p>
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