force not converged

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menguo

force not converged

#1 Post by menguo » Mon Sep 11, 2006 10:23 pm

Hello,

My case is a cell of hydroxylapatite (44 atoms) with a h2o molecule adsorbing.
The INCAR is as following:


NPAR = 1


PREC = accurate
NELM = 40
NELMIN = 4
EDIFF = 1E-03
EDIFFG = -.03
IALGO = 48
LREAL = .TRUE.

Ionic Relaxation
NSW = 120
IBRION = 1
ISIF = 2
ISYM = 1
POTIM = .4
NBANDS = 350

DOS related values:
ISMEAR = 0
SIGMA = .1
RWIGS = 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
LORBIT = 1


AMIX = 0.2
BMIX = 0.0001
MAXMIX = 40
NSIM = 40
ISPIN = 1

I do see the energe converged, but the total-force (ev/angst) at the end of OUTCAR could be around 2 for some atoms (atoms in cell).
I want to know if any parameters should be adjusted to achieve convergence?

Thanks!
~
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Last edited by menguo on Mon Sep 11, 2006 10:23 pm, edited 1 time in total.

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force not converged

#2 Post by admin » Wed Sep 13, 2006 10:02 am

first of all check if each electronic step REALLY is converged before the forces are calculated.
Last edited by admin on Wed Sep 13, 2006 10:02 am, edited 1 time in total.

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