<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:14pt">Thank you Mr. Robert for your kind response.<br>I will include the verbosity='high' and repeat the calculations. However, you made mention that, when i plotted the DOS there is need to shift my Fermi level to zero; that i did not understand very well. My question is, How to shift my Fermi to zero?. Secondly, I always see my Fermi energy at the end of my scf calculation.'' the Fermi energy is -2.0508'', before total energy line. Does it mean -2.0508 is my actual Fermi energy? because the zero point in the DOS graph is just a reference point. Lastly, for my plotting software, i used Qtiplot. Usually, after <span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">my ./dos.x input and output, i take my 'dos' directly to plot my DOS. Therefore, I don't know if you or someone can help with some guide about
it.<br><br>Once again thank you and Best regards.<br></span></span><br><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Shamsu Abubakar</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Postgraduate student</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Department of Physics</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div class="yiv1290220621MsoNormal" style="background:white;"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">University Putra Malaysia</span></span><span
style="font-size:14.0pt;color:black;"></span></div><div><span><br></span></div><div><br></div> <div style="font-family: times new roman, new york, times, serif; font-size: 14pt;"> <div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"> <div dir="ltr"> <font face="Arial" size="2"> <hr size="1"> <b><span style="font-weight:bold;">From:</span></b> Robert Hembree <hembreerofphysics@gmail.com><br> <b><span style="font-weight: bold;">To:</span></b> 'Shamsu Abubakar' <say457@yahoo.co.uk>; 'PWSCF Forum' <pw_forum@pwscf.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Friday, 5 April 2013, 1:17<br> <b><span style="font-weight: bold;">Subject:</span></b> RE: [Pw_forum] Fermi energy reference point shift from 0 to -2<br> </font> </div> <br><div id="yiv1290220621"><style><!--
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--></style><div><div class="yiv1290220621WordSection1"><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">Dear Shamsu</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">Your input file and parameters are fine. When you plot the DOS you need to shift your Fermi level to zero if you want the gap to show up at zero. </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">Add the line</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",
"sans-serif";color:#1F497D;">verbosity = ‘high’ </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">to the control part of your input file and run pw.x again. Then you can grep your output file</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">less scf.out | grep ‘Fermi energy’</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">You should get a line that looks like this:</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",
"sans-serif";color:#1F497D;">the Fermi energy is -1.6709 ev</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">When you plot your DOS, for instance in gnuplot you would now plot</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">plot ‘Graph01.dos’ ($1-(-1.6709)):2 w l</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",
"sans-serif";color:#1F497D;">and you should see your plot with the bandgap and dispersion at zero. </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">When you do these calculations the Fermi level will rarely show up at exactly zero.</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;"> </span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri", "sans-serif";color:#1F497D;">Robert</span></div><div class="yiv1290220621MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",
"sans-serif";color:#1F497D;"> </span></div><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in;"><div class="yiv1290220621MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma", "sans-serif";">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma", "sans-serif";"> pw_forum-bounces@pwscf.org [mailto:pw_forum-bounces@pwscf.org] <b>On Behalf Of </b>Shamsu Abubakar<br><b>Sent:</b> Wednesday, April 03, 2013 8:23 PM<br><b>To:</b> pw_forum@pwscf.org<br><b>Subject:</b> [Pw_forum] Fermi energy reference point shift from 0 to -2</span></div></div></div><div class="yiv1290220621MsoNormal"> </div><div><div id="yiv1290220621"><div><div><div><div class="yiv1290220621MsoNormal" style="background:white;"><span style="font-size:14.0pt;color:black;">Dear <span class="yiv1290220621tab">Q.E Users.</span></span></div></div><div><div
class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">I have a system of 4x4 graphene supercell, comprising 32 carbon atoms. I sucessfully run all the calculations i.e scf,nscf and other postprocessing such as DOS and PDOS. But the main problem i'm facing currently is on the density of state. Usually, i consider zero to be my fermi reference energy point in my ./dos.x input file, forexample,from -10 and 10 as my Emin and Emax respectivily. For pristine graphene,i expect to always see the dispersion at the zero vicinity, showing a semi metallic behavior, but surprisingly, its always moving away from zero to around -2, in the valence band side which i knew is unsual for pristine graphene. However, when i combine graphene with GaAs nanostructure, most of the interesting properties interms of orbitals contributions (PDOS), also resides on similar point -2. That is some of the contributions that are
supposed to be seen at the vicinity of the fermi level, now moved to another point -2. Also, i consider changing the smearing from marzari-vanderbilt to Fermi- Dirac, but similar properties were observed. I decided to consider only 1x1, and 2x2 graphene supercell alone, still similar properties i observed also. In fact, i even consider changing my pseudopotential from pw91 to pbe.rrkjus still no progress. My problem now, i don't know what really causes these shift from 0 to -2. </span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">I attached one of my graphene scf input file for your verification and advice.</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span style="font-size:14.0pt;color:black;"> </span></div></div><div><div
class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;"> &CONTROL</span></span><span style="font-size:14.0pt;color:black;"><br><span class="yiv1290220621tab"> title = 'Graphene monolayer01',</span><br><span class="yiv1290220621tab"> prefix = 'Graph01',</span><br><span class="yiv1290220621tab"> calculation = 'scf' ,</span><br><span class="yiv1290220621tab"> restart_mode = 'from_scratch' ,</span><br><span
class="yiv1290220621tab"> outdir = '/home//???/espresso-4.1.2/bin/' ,</span><br><span class="yiv1290220621tab"> pseudo_dir = '/home//???/???/espresso-4.1.2/upf_files/' ,</span><br><span class="yiv1290220621tab"> </span><br><span class="yiv1290220621tab"> tstress = .true. ,</span><br><span class="yiv1290220621tab"> tprnfor = .true. ,</span><br><span class="yiv1290220621tab"> /</span><br><span
class="yiv1290220621tab"> &SYSTEM</span><br><span class="yiv1290220621tab"> ibrav = 4,</span><br><span class="yiv1290220621tab"> celldm(1) = 18.59490373,</span><br><span class="yiv1290220621tab"> celldm(3) = 1.80,</span><br><span class="yiv1290220621tab"> nat = 32,</span><br><span class="yiv1290220621tab"> ntyp =
1,</span><br><span class="yiv1290220621tab"> ecutwfc = 34.D0 ,</span><br><span class="yiv1290220621tab"> tot_charge = 0.000000,</span><br><span class="yiv1290220621tab"> occupations = 'smearing' ,</span><br><span class="yiv1290220621tab"> degauss = 0.02 ,</span><br><span class="yiv1290220621tab"> smearing = 'fermi-dirac' ,</span><br><span
class="yiv1290220621tab"> </span><br><span class="yiv1290220621tab"> /</span><br><span class="yiv1290220621tab"> &ELECTRONS</span><br><span class="yiv1290220621tab"> conv_thr = 1.D-8 ,</span><br><span class="yiv1290220621tab"> mixing_beta = 0.7D0 ,</span><br><span class="yiv1290220621tab"> /</span><br><span class="yiv1290220621tab">ATOMIC_SPECIES</span><br><span class="yiv1290220621tab"> C 12.00000 C.pw91-van_ak.UPF </span><br><span class="yiv1290220621tab"> </span><br><span class="yiv1290220621tab">ATOMIC_POSITIONS (angstrom)</span><br><span
class="yiv1290220621tab">C 1.229999657 0.709326753 1.999999753</span><br><span class="yiv1290220621tab">C 2.459999165 1.419486000 1.999999874</span><br><span class="yiv1290220621tab">C 3.689999208 0.709327391 1.999999822</span><br><span class="yiv1290220621tab">C 4.920000000 1.419486496 1.999999944</span><br><span class="yiv1290220621tab">C 4.920000000 2.839880146 2.000000125</span><br><span class="yiv1290220621tab">C 6.149999990 3.549976521 1.999999907</span><br><span class="yiv1290220621tab">C 3.690000010
3.549976521 1.999999907</span><br><span class="yiv1290220621tab">C 2.459999764 2.839879152 2.000000067</span><br><span class="yiv1290220621tab">C 6.150000792 0.709327391 1.999999822</span><br><span class="yiv1290220621tab">C 7.380000835 1.419486000 1.999999874</span><br><span class="yiv1290220621tab">C 7.380000236 2.839879152 2.000000067</span><br><span class="yiv1290220621tab">C 8.610000005 3.549975943 1.999999891</span><br><span class="yiv1290220621tab">C 8.609999654 4.970023341 2.000000208</span><br><span
class="yiv1290220621tab">C 9.840000000 5.680120078 2.000000200</span><br><span class="yiv1290220621tab">C 7.379999382 5.680120770 2.000000152</span><br><span class="yiv1290220621tab">C 6.149999800 4.970024086 2.000000150</span><br><span class="yiv1290220621tab">C 4.920000000 5.680121474 2.000000132</span><br><span class="yiv1290220621tab">C 3.690000200 4.970024086 2.000000150</span><br><span class="yiv1290220621tab">C 8.610000343 0.709326753 1.999999753</span><br><span class="yiv1290220621tab">C 9.840000000
1.419485253 1.999999874</span><br><span class="yiv1290220621tab">C 9.840000000 2.839878353 2.000000070</span><br><span class="yiv1290220621tab">C 11.069999995 3.549975943 1.999999891</span><br><span class="yiv1290220621tab">C 11.070000346 4.970023341 2.000000208</span><br><span class="yiv1290220621tab">C 12.300000618 5.680120770 2.000000152</span><br><span class="yiv1290220621tab">C 12.300001137 7.100514050 2.000000166</span><br><span class="yiv1290220621tab">C 13.530000464 7.810673002 1.999999744</span><br><span class="yiv1290220621tab">C
11.070000830 7.810672948 1.999999928</span><br><span class="yiv1290220621tab">C 9.840000000 7.100514025 2.000000287</span><br><span class="yiv1290220621tab">C 8.609999170 7.810672948 1.999999928</span><br><span class="yiv1290220621tab">C 7.379998863 7.100514050 2.000000166</span><br><span class="yiv1290220621tab">C 6.149999536 7.810673002 1.999999744</span><br><span class="yiv1290220621tab">C 4.920000000 7.100514261 2.000000041</span><br><span class="yiv1290220621tab"> </span><br><span class="yiv1290220621tab">K_POINTS automatic </span><br><span class="yiv1290220621tab">
6 6 1 0 0 0 </span></span></div></div><div><div class="yiv1290220621MsoNormal"><span style="font-size:14.0pt;color:black;"> </span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Thank you for your kind response.</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span style="font-size:14.0pt;color:black;"> </span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Shamsu Abubakar</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Postgraduate student</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div><div
class="yiv1290220621MsoNormal"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">Department of Physics</span></span><span style="font-size:14.0pt;color:black;"></span></div></div><div class="yiv1290220621MsoNormal" style="background:white;"><span class="yiv1290220621tab"><span style="font-size:14.0pt;color:black;">University Putra Malaysia</span></span><span style="font-size:14.0pt;color:black;"></span></div></div></div></div></div></div></div></div><br><br> </div> </div> </div></body></html>