[Pw_forum] conversence problem in vc-relax (Atom Mass in relaxation)
Yukihiro Okuno
okunoyukihiro2000 at yahoo.co.jp
Sat Sep 8 18:02:49 CEST 2007
Dear PWScf Users.
I'm Yukihiro Okuno.
I had posted about the Atom Mass in vc-relax, and thank you for the responces.
We set same atom mass 20.0 ( average of atom mass), and do vc-relax calculation as
the following input file,
&control
calculation = 'vc-relax',
restart_mode = 'from_scratch',
pseudo_dir = '/pseudo/',
outdir = './',
prefix='vc-test'
nstep = 100
etot_conv_thr = 1.0D-5
forc_conv_thr = 1.0D-4
dt = 80.0
tstress = .true.
tprnfor = .true.
/
&system
ibrav=6
celldm(1)=6.83994507291
celldm(3)=1.09801321247
nat=5
ntyp=3
nbnd=26
ecutwfc=60.0
ecutrho = 600.0
occupations = 'fixed'
degauss=0.00
/
&electrons
conv_thr = 1e-10,
mixing_beta=0.3,
/
&IONS
ion_dynamics='damp'
bfgs_ndim=3
pot_extrapolation = "second_order"
wfc_extrapolation = "second_order"
/
&CELL
cell_dynamics = 'damp-w',
press = 0.0
wmass = 0.02
/
But the calculation is not conversed and oscillate. The system has only five atoms
and simple P4mm perovskite structure.
I had change wmass as default value, but the convergence is not achieved.
Is it too hard to converse to set forc_conv_thr = 1.0D-4 in VC-relax calculation ?
( I want to get severe internal atomic coordinate, and forc_conv_thr=1.0D-3 is not
sufficient.) Simple atomic internal relaxation, I can get converged result.
The stress and total force of output file is as follow.
stress values ,,
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.13
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -2.09
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -1.17
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.60
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.07
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.37
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.84
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.95
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 1.07
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 1.22
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 1.36
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 1.47
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 1.55
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.96
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.65
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.39
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.20
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.04
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.08
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.13
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.13
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.63
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.89
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -1.05
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -1.04
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -1.13
and The total force,
Total force = 0.000512 Total SCF correction = 0.000057
Total force = 0.000499 Total SCF correction = 0.000063
Total force = 0.000472 Total SCF correction = 0.000024
Total force = 0.000411 Total SCF correction = 0.000022
Total force = 0.000385 Total SCF correction = 0.000053
Total force = 0.000527 Total SCF correction = 0.000012
Total force = 0.000487 Total SCF correction = 0.000188
Total force = 0.000572 Total SCF correction = 0.000010
Total force = 0.000537 Total SCF correction = 0.000016
Total force = 0.000484 Total SCF correction = 0.000016
Total force = 0.000440 Total SCF correction = 0.000007
Total force = 0.000407 Total SCF correction = 0.000017
Total force = 0.000369 Total SCF correction = 0.000016
Total force = 0.000391 Total SCF correction = 0.000045
Total force = 0.000552 Total SCF correction = 0.000015
Total force = 0.000569 Total SCF correction = 0.000130
Total force = 0.000683 Total SCF correction = 0.000026
Total force = 0.000623 Total SCF correction = 0.000025
Total force = 0.000544 Total SCF correction = 0.000020
Total force = 0.000404 Total SCF correction = 0.000015
Total force = 0.000280 Total SCF correction = 0.000028
Total force = 0.000219 Total SCF correction = 0.000011
Total force = 0.000348 Total SCF correction = 0.000039
Total force = 0.000552 Total SCF correction = 0.000015
Total force = 0.000688 Total SCF correction = 0.000019
Total force = 0.000741 Total SCF correction = 0.000013
Total force = 0.000723 Total SCF correction = 0.000013
Total force = 0.000638 Total SCF correction = 0.000018
Total force = 0.000504 Total SCF correction = 0.000017
Total force = 0.000368 Total SCF correction = 0.000029
Total force = 0.000256 Total SCF correction = 0.000020
Total force = 0.001173 Total SCF correction = 0.000016
Total force = 0.001841 Total SCF correction = 0.000271
Total force = 0.001924 Total SCF correction = 0.000220
Total force = 0.002328 Total SCF correction = 0.000057
Total force = 0.002448 Total SCF correction = 0.000019
Total force = 0.002318 Total SCF correction = 0.000016
Total force = 0.002004 Total SCF correction = 0.000018
Total force = 0.001547 Total SCF correction = 0.000022
Total force = 0.001029 Total SCF correction = 0.000026
Total force = 0.000669 Total SCF correction = 0.000015
Total force = 0.002834 Total SCF correction = 0.000206
Total force = 0.003057 Total SCF correction = 0.000170
Total force = 0.001864 Total SCF correction = 0.000273
Total force = 0.001107 Total SCF correction = 0.000101
Total force = 0.000870 Total SCF correction = 0.000021
Total force = 0.000355 Total SCF correction = 0.000068
Total force = 0.000613 Total SCF correction = 0.000114
Total force = 0.000484 Total SCF correction = 0.000038
Total force = 0.000338 Total SCF correction = 0.000180
Total force = 0.000372 Total SCF correction = 0.000125
Total force = 0.000460 Total SCF correction = 0.000028
Total force = 0.000482 Total SCF correction = 0.000014
Total force = 0.000528 Total SCF correction = 0.000018
Total force = 0.000652 Total SCF correction = 0.000008
Total force = 0.000729 Total SCF correction = 0.000017
Total force = 0.000740 Total SCF correction = 0.000013
Total force = 0.000684 Total SCF correction = 0.000005
Total force = 0.000573 Total SCF correction = 0.000005
Total force = 0.000446 Total SCF correction = 0.000012
Total force = 0.000369 Total SCF correction = 0.000010
Total force = 0.000408 Total SCF correction = 0.000005
Total force = 0.000602 Total SCF correction = 0.000044
Total force = 0.000897 Total SCF correction = 0.000015
Total force = 0.001145 Total SCF correction = 0.000020
Total force = 0.001247 Total SCF correction = 0.000004
Total force = 0.001348 Total SCF correction = 0.000050
Sincerely.
----
Yukihiro Okuno okunoyukihiro2000 at yahoo.co.jp
More information about the users
mailing list