[Pw_forum] scf stops after finishing 100 iteration

[Dimpy Sharma]

Hi Quantum espresso users,

I tired to perform scf calculation but it shows me the following error
     'convergence NOT achieved after 100 iterations: stopping'

However the nscf calculation and projected density of states run successfully, why is this so?

My input file is as follows

&CONTROL
     calculation ='scf' 
    restart_mode = 'from_scratch' 
          outdir = '/sfiwork/dsharma/PDOSSilane/PDOSsi/si_wfc'
      pseudo_dir = '/sfiwork/dsharma/QE_Pseudos/'
          prefix = 'si'
         tstress = .true.
         tprnfor = .true.
   etot_conv_thr = 1.D-4
   forc_conv_thr = 1.D-3
           nstep = 600
          wf_collect =.true.
 /
 &SYSTEM
        ibrav = 0
    celldm(1) =7.4088
          nat = 6
         ntyp = 1
      ecutwfc = 40
      ecutrho = 160.0
         nbnd = 12
 /
 &ELECTRONS
    diagonalization ='david'
        mixing_mode = 'plain'
           conv_thr = 1.0d-6
        mixing_beta = 0.7
/
&IONS
 /
&CELL
 cell_dynamics='none'
 /
CELL_PARAMETERS cubic 
     1.000000000    0.000000000    0.000000000 
     0.000000000    2.000000000    0.000000000 
     0.000000000    0.000000000    2.000000000 
ATOMIC_SPECIES
   Si   28.08600  Si.pz-vbc.UPF
ATOMIC_POSITIONS angstroms 
 Si        2.95020       -0.66592       -0.12341
 Si        4.90939        0.61749        0.11358
 Si        0.99475        0.65272       -0.16138
 Si       -0.98472       -0.62740       -0.15123
 Si       -2.94624        0.68229       -0.12124
 Si       -4.89549       -0.61534        0.11905
 K_POINTS automatic 
  4 1 1   0 0 0 

Can anybody give me any suggestions?

Thanks 

Dimpy

Dimpy Sharma,
PhD
Electronics Theory  Group
UCC,Cork
Ireland


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