I'm having trouble getting VASP to do a simple configuration relaxation calculation.
I've been running VASP for a couple of years now and we've recently updated our cluster and I'm getting a strange output from the code that I've never gotten before:
CG: scaled line search X= 0.0000 F= -23.0335 dX= 1.0000
CG: unscaled line search X= 0.0000 F= -21.8506 dX= 1.0541
The problem is as follows: I'm trying to do a simple relaxation calculation to figure out the ground state configuration and energy of a system, however, instead of going through the many ionic and electronic relaxations it stops after the first ionic step. It's doing this for many configurations and so I know it has nothing to do with that.
Below is my INCAR:
Electronic minimization
PREC = NORM
GGA = 91
VOSKOWN = 1
IALGO = 48
ISYM = 0
ISPIN = 2
LREAL = Auto
NELM = 300
EDIFF = 1E-4
Ionic relaxation
EDIFFG = 1E-3
NSW = 100
IBRION = 2
POTIM = 0.5
DOS related values
ISMEAR = 2 ; SIGMA=0.2
NPAR = 1
Energy values for adsorption comparison
ENMAX = 395.994
RWIGS = 0.5
My output is as below, note it stops at the first ionic step:
N E dE d eps ncg rms rms(c)
RMM: 1 0.631782272979E+01 0.63178E+01 -0.13524E+01 10 0.232E+01
.......................
.......................
.......................
RMM: 25 -0.111316798268E+01 -0.11573E-03 0.00000E+00 18 0.000E+00 0.267E-04
RMM: 26 -0.111323473291E+01 -0.66750E-04 0.00000E+00 18 0.000E+00
1 F= -.11132347E+01 E0= -.11146113E+01 d E =-.111323E+01 mag= 1.0000
trial: gam= 0.00000 g(F)= 0.000E+00 g(S)= 0.000E+00 ort = NaN (trialstep = 0.100E+01)
search vector abs. value= 0.000E+00
CG: scaled line search X= 0.0000 F= 0.0000 dX= 1.0000
CG: unscaled line search X= 0.0000 F= NaN dX= 0.0000
reached required accuracy - stopping structural energy minimisation
writing wavefunctions
I've never seen these last couple of lines that state "CG: scaled...." and "CG: unscaled....". I suspect this has something to do with why the code is prematurely terminating. Can anyone tell me what these CG flags mean? Can anyone help me get back to a simple relaxation?
Thanks!
Regards,
mff7d
CG scaled line search
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CG scaled line search
Last edited by mff7d on Wed Sep 02, 2009 6:20 pm, edited 1 time in total.
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CG scaled line search
which code version do you use, I have not found this output line in
any of the standard vasp.4.6 releases. Maybe the code has been
modified?
any of the standard vasp.4.6 releases. Maybe the code has been
modified?
Last edited by admin on Mon Oct 12, 2009 10:44 am, edited 1 time in total.