[Pw_forum] graphene workfunction

[Chad Junkermeier]

Hi,
  I am trying to compute the workfunction of graphene.  I saw that someone else has been able to compute it and get reliable numbers ().  After looking at the examples and what has been written in the forums my best guess as to the general form of the file to run pp.x (before running average.x) is given here.


&inputPP
   outdir='/workspace/junky/WFC_2/tmp',
   plot_num=11
   filplot = 'WFC_2.2.pot'
  prefix='WFC_2'
/
&plot
   iflag=3,
   output_format=3,
   nx=10,
   ny=10,
   nz =5,
/

My problem is that this is taking a really long time to run; much, much longer than the corresponding singlepoint SCF calculation ran using the same number of processors.  At this point, the pp.x has been running for 43 hours.  I can't believe that this is normal.  Here are the last couple of lines from the pp.x output file:


     Writing data to file  WFC_2.2.pot
     Reading data from file  WFC_2.2.pot


What is a normal length of time for this to run (I am running on 48 processors)?  Is my input for pp.x really screwed up?  Is pp.x just sitting there eating up computer time and not computing anything?

Thank you for your help.


Chad Junkermeier, Ph.D.
NRC Post-Doctoral Associate
Naval Research Laboratory




&CONTROL
  calculation = "scf",
  prefix='WFC'
  restart_mode='from_scratch',
  pseudo_dir  = "/app/espresso/pseudo",
  outdir      = "/workspace/junky/WFC/tmp",
/
&SYSTEM
  ibrav       = 4,
  celldm(1)   = 9.300,
  celldm(3)   = 5.00000000000000000000,
  nat         = 8,
  ntyp        = 1,
  ecutwfc     = 300.0,
  occupations = "smearing",
  smearing    = "methfessel-paxton",
  degauss     = 0.05,
/
&ELECTRONS
  conv_thr    = 1.D-6,
  mixing_beta = 0.3,
/
ATOMIC_SPECIES
C  6.0 C.pbe-van_ak.UPF
ATOMIC_POSITIONS crystal
C       0.0     0.0     0.0
C       0.1666666666666667      0.3333333333333333      0.0
C       0.0     0.5     0.0
C       0.1666666666666667      0.8333333333333333      0.0
C       0.5     0.0     0.0
C       0.6666666666666667      0.3333333333333333      0.0
C       0.5     0.5     0.0
C       0.6666666666666667      0.8333333333333333      0.0
K_POINTS automatic
4 4 1  0 0  0



      
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