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<FONT face="Courier New" size=3>Dear all,</FONT><BR>
<FONT face="Courier New" size=3></FONT> <BR>
<FONT face="Courier New" size=3>(1) First of all sorry to bombard you with a lot of questions but I am trying to perform the electron phonon calculation of monolayer graphene and I am facing some problems. when performing the ph.x command, after some time, I get an error:</FONT><BR>
<BR>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3>from elphsum : error #<SPAN style="mso-spacerun: yes"> </SPAN>2<BR><SPAN style="mso-spacerun: yes"> </SPAN>q is not a vector in the dense grid<BR><SPAN style="mso-spacerun: yes"> </SPAN>%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<BR><BR><SPAN style="mso-spacerun: yes"> </SPAN>stopping ...</FONT><BR></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'">This is when trying to do calculations for one particular point. my input file is the following:</SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"></SPAN> </P><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'">
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3>Electron-Phonon interaction for monolayer graphene<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>&inputph<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>tr2_ph=1.0d-14,<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>prefix='elphmonograph',<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>fildvscf='mgraphdv',<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>amass(1)=12.0107,<SPAN style="mso-spacerun: yes"> </SPAN><o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>outdir='/tmp/results_MOUJAES/',<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>fildyn='elphmgraph.dyn',<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>elph=.true.,<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>trans=.true.,<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>ldisp=.true.<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>nq1=8, nq2=8, nq3=1<SPAN style="mso-spacerun: yes"> </SPAN><o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"><SPAN lang=EN-GB style="FONT-FAMILY: 'Courier New'"><FONT size=3><SPAN style="mso-spacerun: yes"> </SPAN>/<o:p></o:p></FONT></SPAN></P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">I have tried with lesser points like say nq1=2, nq2=2, nq3=1 and I did not get such an error. </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">(2) My second question is about lambda.x .I have read the example in the QE package but have not really understood it fully. Can anyone briefly explain to me or just point out where there is more explanation about this executable..I fully understtod what it does though..</P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">Regards and thanks for your time</P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">Elie Moujaes</P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">University of Nottingham</P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">NG7 2RD</P>
<P class=MsoPlainText style="MARGIN: 0in 0in 0pt">UK</P></SPAN> </body>
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