Problems with elphon_shuffle_wrap during epw run

[chwolf]

Dear all!

I have compiled the latest qe 6.0 with epw and I have successfully run the test suite using mpirun -np 6 npool 6.

Then I tried to move to a material I am currently studying (CsPbBr3). All the calculations are done on rather coarse grids for testing. My goal is to evidence a certain interaction between electron and phonon that I think I see from spectroscopy. I am an experimentalist so please use simple language...

scf on unshifted 6 6 6 grid
ph on nq= 4 4 4

ONCV potentials in GGA-PBE were used. I read on the board here that that *should* work without guarantees.

this gives 18 q-points

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     (  18q-points):
       N         xq(1)         xq(2)         xq(3) 
       1   0.000000000   0.000000000   0.000000000
       ...
      17  -0.468137399   0.234068683  -0.468137399
      18  -0.468137399  -0.468137365  -0.468137399

then I run a coarse scf 4x4x4 and nscf on a 6x6x6 grid resulting in 216 points (I use nosym=.true. to make sure qe doesnt change into negative coordinates here).

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  216
    1   0.0000000  0.0000000  0.0000000   1.00
    2   0.1666667  0.0000000  0.0000000   6.00
    3   0.3333333  0.0000000  0.0000000   6.00
    4   0.5000000  0.0000000  0.0000000   3.00
    5   0.6666667  0.0000000  0.0000000   0.00   3
....

after using pp.py to copying the necessary files I run epw.

it runs until the wannier part where it throws me an error

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At line 200 of file elphon_shuffle_wrap.f90 (unit = 5, file = 'stdin')
Fortran runtime error: End of file

the corresponding segment tells me:

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 IF (mpime.eq.ionode_id) then
    DO iq = 1, nqc_irr
      READ (5,*) xqc_irr (:,iq), wqlist_irr (iq)
    ENDDO
  ENDIF

so I guess it has some problem reading some data but I gave the q-points exactly as in the ph.x output.

If someone could help me out here it would be greatly appreciated!

Yours,
Chris


EPW Input

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--
&inputepw
  prefix      = 'cspbbr3'
  amass(1)    = 132.90500
  amass(2)    = 207.20000
  amass(3)    = 79.90400
  outdir      = './'

  elph        = .true.
  kmaps       = .false.
  epbwrite    = .true.
  epbread     = .false.

  epwwrite    = .true.
  epwread     = .false.

  nbndsub     =  8
  nbndskip    =  10

  wannierize  = .true.
  num_iter    = 300
  !dis_win_max = 26
  !dis_win_min = 0
  !dis_froz_min= 0
  !dis_froz_max= 5
  proj(1)     = 'random'


  iverbosity  = 0

  elecselfen  = .true.
  phonselfen  = .true.
  a2f         = .true.

  parallel_k  = .true.
  parallel_q  = .false.

  fsthick     = 6 ! eV
  eptemp      = 2000 ! K
  degaussw    = 1.0  ! eV
  degaussq    = 0.05 ! meV

  dvscf_dir   = './save'
  filukk      = './cspbbr3.ukk'
 
  nkf1        = 8 !fine electron grid
  nkf2        = 8
  nkf3        = 8

  nqf1        = 8 !fine phonon grid
  nqf2        = 8
  nqf3        = 8

  nk1         = 6 !nscf_epw = corresponds to the nscf
  nk2         = 6
  nk3         = 6

  nq1         = 4  !ph.in nq1..  corresponds to the nqs list.
  nq2         = 4
  nq3         = 4
 /
      18 cartesian
         0.000000000   0.000000000   0.000000000
          0.000000000   0.000000000   0.234068700
          0.000000000   0.000000000  -0.468137399
          0.000000000   0.234068683   0.000000000
          0.000000000   0.234068683   0.234068700
          0.000000000   0.234068683  -0.468137399
          0.000000000  -0.468137365   0.000000000
          0.000000000  -0.468137365   0.234068700
          0.000000000  -0.468137365  -0.468137399
         0.234068700   0.000000000   0.234068700
         0.234068700   0.000000000  -0.468137399
         0.234068700   0.234068683   0.234068700
         0.234068700   0.234068683  -0.468137399
         0.234068700  -0.468137365   0.234068700
         0.234068700  -0.468137365  -0.468137399
        -0.468137399   0.000000000  -0.468137399
        -0.468137399   0.234068683  -0.468137399
        -0.468137399  -0.468137365  -0.468137399

EPW output

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MMN calculated

     Running Wannier90

     Wannier Function centers (cartesian, alat) and spreads (ang):

     (   1.06545   0.97701   1.04084) :   0.97133
     (   0.62096   0.51266   0.53918) :   1.54838
     (   0.01670   0.01975   0.09115) :   0.96668
     (   0.51907   0.49954   0.27158) :   2.00449
     (   1.05265   0.46287   0.49065) :   0.90938
     (   0.60080  -0.00267   0.60167) :   0.94371
     (   0.61686   0.53875   1.03068) :   1.22948
     (   0.48812   0.46477   1.04193) :   1.23779

     -------------------------------------------------------------------
     WANNIER      :    401.95s CPU    403.95s WALL (       1 calls)
     -------------------------------------------------------------------
-------------------------------------------------------
Primary job  terminated normally, but 1 process returned
a non-zero exit code.. Per user-direction, the job has been aborted.
-------------------------------------------------------
--------------------------------------------------------------------------
mpirun detected that one or more processes exited with non-zero status, thus causing
the job to be terminated. The first process to do so was:

  Process name: [[50256,1],0]
  Exit code:    2
--------------------------------------------------------------------------

[carla.verdi]

Dear Chris

You did everything correctly, however the list of q points in the epw.in needs to be
xq(1) xq(2) xq(3) wq
i.e. you are missing the weight wq. In fact wq is read from the input but not used in the calculation (historical reasons..), so it will probably become deprecated in the future.

Best
Carla

[chrisewolf]

Dear Carla!

Thank you very much, I have misinterpreted a post on weights mentioning they are not being "used" as they would not be read... mea culpa!


Yours,
Chris

PS: I tried to make a signature but the function is not activated in my UCP!