[Pw_forum] Grain boundary Scf calculations stopping

[Elie Moujaes]

Dear All,
I am running scf calculations for a 72 Carbon atom grain boundary system. I had problems in the convergence in the past with the c_bands error erupting and the program stopping. The calculations have been stopping i guess due to the lack of enough memory so I tried several things like reducing ecutwfc to 30 but had to put a value of ecutrho equal to 200 to ensure a small negative charge density. I have also used diago_david_ndim=2. The calculations are still stopping (they stopped at the 10th iteration now) and am still getting some messages from c_bands; Here is a part of the input. Can anyone please advise me of what to change to make the calculations work because the system is already large (288 electrons) and takes scf calculations a few days to be done.
Thank You
Elie MoujaesUniversity of NottinghamNG7 2RDUK




control
    prefix='GBdensity',
    calculation='scf',
    restart_mode='from_scratch',
    pseudo_dir = '/exp/home/caiapo/emoujaes/espresso/espresso-4.1.3/pseudo/',
    outdir='/exp/home/caiapo/emoujaes/espresso/espresso-4.1.3/pseudo',
          
 /
 &system    
    ibrav=
 0, celldm(1) =1.889725989, nat=72, ntyp= 1, ecutwfc =30.0, ecutrho = 200.D0, nosym=.true.,occupations='smearing', smearing='mv', degauss=0.01
/
 &electrons
    conv_thr=1.D-4,     
    mixing_beta=0.3D0,    mixing_mode='local-TF'    diago_david_ndim=2,  

    
 /
  
CELL_PARAMETERS (alat)
  29.416600000   0.000000000   0.000000000
   0.000000000   6.609900000   0.000000000
   0.000000000   0.000000000  33.000000000
 
     
ATOMIC_SPECIES
 C  12.0107  C.pz-rrjus.UPF
  
ATOMIC_POSITIONS (angstrom)
C     -17.267939   -5.262892   -0.000002  
C     -17.658134   -3.893047   -0.000002  
C     -16.648186   -2.892145    0.000000  
C     -16.979016   -1.481403   -0.000001  
C     -15.822497   -7.188651    0.000003  
C     -15.974769   -5.758011    0.000001
C     -14.931838   -4.783788   -0.000002
C     -15.260133   -3.372206   -0.000003
C     -14.164353   -2.443247   -0.000001
C     -14.448789   -1.038033    0.000001
C     -13.357280   -6.694629   -0.000003
C     -13.589274   -5.266428   -0.000006
C     -12.507820   -4.324210   -0.000003
C     -12.797007   -2.912572   -0.000003
C     -11.713425   -1.967554    0.000002
C     -11.996028   -0.554049    0.000001
C     -10.908497   -6.218111   -0.000001
C     -11.153648   -4.798395    0.000000
C     -10.348701   -2.439065    0.000002
C     -10.066097   -3.852576   -0.000001
C      -9.265132   -1.494029   -0.000001
C      -9.554319   -0.082394    0.000000
C      -8.472857   -5.750083   -0.000002
C      -8.704854   -4.321888    0.000001
C      -7.613348   -3.368592    0.000001
C      -7.897799   -1.963373   -0.000003
C      -6.802030   -1.034415    0.000000
C      -7.130288    0.377174   -0.000002
C      -6.239632   -3.827864   -0.000001
C      -6.087349   -5.258489    0.000002
C      -5.083140   -2.925203    0.000000
C      -5.413953   -1.514463    0.000000
C      -4.403993   -0.513566    0.000002
C      -4.794134    0.856288    0.000002
C      -3.676893   -4.887701   -0.000001
C      -3.676919   -3.479951   -0.000003
C      -2.270708   -2.925222   -0.000002
C      -2.949816   -0.513582   -0.000002
C      -1.939871   -1.514481    0.000001
....
.....
..... 
K_POINTS automatic
4 4 1  0 0 0
 		 	   		  
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