[Pw_forum] PW stops while Total energy change is greater than etot_conv_thr.

[Tsung-Lung Li]

Dear QE Friends:

I run PW with vc-relax. (The input file is attached after this message)

It runs OK and produces an out file, t.log

$ grep ! t.log
!    total energy              =    -591.32561856 Ry
!    total energy              =    -591.32682605 Ry
!    total energy              =    -591.32834551 Ry
!    total energy              =    -591.32866341 Ry
!    total energy              =    -591.32877610 Ry
!    total energy              =    -591.32884710 Ry
!    total energy              =    -591.32892160 Ry
!    total energy              =    -591.32897578 Ry
!    total energy              =    -591.32900165 Ry
!    total energy              =    -591.32903371 Ry
!    total energy              =    -591.32905361 Ry
!    total energy              =    -591.32906413 Ry
!    total energy              =    -591.32907290 Ry
!    total energy              =    -591.32908493 Ry
!    total energy              =    -591.32909828 Ry
!    total energy              =    -591.32910938 Ry  <--- Total energy 
change = 1.1100e-05
!    total energy              =    -591.32966974 Ry  <--- Total energy 
change = -5.6036e-04

etot_conv_thr = 1.0D-4 and forc_conv_thr = 1.0D-3  are set in the input

Why QE stops at a step with Total energy change = -5.6036e-04 (where 
etot_conv_thr = 1.0D-4 is
not satisfied) ?

&control
   title = 'Gypsum (CaSO4.2H20 Z=2)'
   prefix = 'gyp-pbe-psl100-AM93-ibrav-13-0.0001G-vc-r-no'
   outdir = 
'/work2/u2equa02/tempdir/gyp-pbe-psl100-AM93-ibrav-13-0.0001G-vc-r-no'
   pseudo_dir = '/home/u2equa02/quantumhome/pseudo/mineral'
   calculation = 'vc-relax'
   restart_mode = 'from_scratch'
   disk_io = 'low'
   verbosity = 'high'
   wf_collect = .true.
   tstress = .true.
   tprnfor = .true.
   nstep = 300
   etot_conv_thr = 1.0D-4
   forc_conv_thr = 1.0D-3
/
&system
   ibrav = -13
   celldm(1) = 11.86181088389489 ! bohr
   celldm(2) = 2.41851202803887
   celldm(3) = 0.903616377250279
   celldm(5) = -0.408489773780522
   ntyp = 4
   nat = 24
   ecutwfc = 50
   ecutrho = 344
/
&electrons
   electron_maxstep = 200
   conv_thr = 1.0D-6
   startingpot = 'atomic'
   startingwfc = 'atomic+random'
   mixing_mode = 'plain'
   mixing_beta = 0.7
   mixing_ndim= 8
   diagonalization = 'david'
/
&ions
   ion_dynamics = 'bfgs'
/
&cell
   press = 0.001D0  ! kbar
   press_conv_thr = 0.5D0  ! kbar
/

ATOMIC_SPECIES
    Ca   40.0780000000  Ca.pbe-spn-rrkjus_psl.1.0.0.UPF
     S   32.0650000000  S.pbe-n-rrkjus_psl.1.0.0.UPF
     O   15.9994000000  O.pbe-n-rrkjus_psl.1.0.0.UPF
     H    1.0079000000  H.pbe-rrkjus_psl.1.0.0.UPF

ATOMIC_POSITIONS crystal
Ca       0.832229984   0.167770016   0.250000000
Ca       0.167770016   0.832229984   0.750000000

.....



K_POINTS automatic
4 4 4 0 0 0