[Pw_forum] neb

[Tone Kokalj]

On Thu, 2007-11-22 at 11:28 -0500, Axel Kohlmeyer wrote:
> On Thu, 22 Nov 2007, ÇÍÓÇä ÚÑíÞÇÊ wrote:
> 
> IA> Hi 
> IA> below is neb output file ,it`s still running ,my
> IA> question can this neb job converged ? If no,how could
> 
> hi!
> 
> how should anybody be able to tell it from the little
> information you provide???

I agree with Axel, but at least something can be said from the Ihsan's
provided data.

Usually in NEB calculation, one connects the two local minima (i.e. 1st
and last image). But this is not the case in Ihsan' calculation as 1st
and last image have large total force: 1.707793  and 3.415599 eV/Angs,
respectively. 

It is possible to optimize them on the fly by setting the first_last_opt
= .true. , but
my suggestion is to optimize these first by the bfgs 'relax' run.

Otherwise the errors on the order of 1 eV/Angs in 5th iteration is
nothing awkward. The NEB calculation may easily take as long as 100
iteration (yes, the NEB is a CPU time monster).

Regards, Tone
--
J. Stefan Institute, Ljubljana, Slovenia