UT theoretical chemistry code forum

OK I think I solved the problem.

It turned out that I didn't read the dynmat page more carefully.


I had to set IBRION=3 but my calculation was set as IBRION=2.

Strange that other jobs worked fine though.

Hi all

I'm trying run a dynamical matrix run to get the ZPE corrections.

When running the job, I'm getting errors with NaNs appearing in the output.

I'm running the job with 9 DOFs, 3 images with NSW=4.

Could anyone explain why this error appears and suggest a way to avoid this error?

I check ...

Hi all,

I'm trying to do a zero-point energy evaluation on metal slab-adsorbant system.

I'm trying to understand DISPLACECAR generation scripts.

So I think I know what the first 4 numbers are in the DISPLACECAR file, but I'm not really sure what the last number means.

Like:

[dx] [dy] [dz ...

Thank you for the answer.

Regarding the distance, how close the distance between the images should be? (in other words, how many digits should I consider?)

Is 0.48 and 0.50 calculated from dist.pl close enough?

Thank you Prof. Henkelman.

Could you elaborate on making a band out of two path segments?

I can't find any parameters defining a band. Do you mean constructing N images using the Initial state and the TS guess and construct Max_image - N images using the TS guess and Final state?

Hi all,

If the inital images constructed from nebmake.pl doesn't look right, would there be much problem if I tweak the constructed images manually to make a more reasonable path?

In that case, is there anything I need to consider when changing the images?

Thanks

M.-C.

Thank you for the answer prof. Henkelman.

Some additional questions:

1. What does exactly "run the FIRE calculation longer" mean? Are you suggesting lowering the time step and/or lowering the EDIFFG of the FIRE job?

2. As I look at the images, the distance between the starting geometry of the ...

Hi all,

I'm doing a CI-NEB calculation. Just wanted to check if this procedure makes sense.

At first, I did a continuous FIRE(EDIFFG = -1.0) -> L-BFGS(EDIFF = -0.15) job using the default TIMESTEP parameters.

The FIRE step was taking some time and when consulting the nebef.pl result, I noticed ...

Thank you for the reply.

I noticed there's another executable and now it seems to be working.

======================================
...
VTST: version 3.1, (03/28/14)

CHAIN: initializing optimizer

OPT: Using VASP QUASI-newton optimizer
CHAIN: Read ICHAIN 0
CHAIN: Running the NEB
NEB: SPRING ...

Hi all,

I'm doing a NEB calculation on oxygen dissociation.

As I checked the energies, it seems to be oscillating(or 'stuck' I'd say).

(The cnvg-f.txt file in the attachment is the result from
grep "F=" stdout
to look at E and dE)

Is this or common thing or should I rerun the calculation with ...

Thank you for the answers.

I'm trying to set up a queue submit file doing CI-NEB-FIRE with EDIFFG = --1.0 to CI-NEB-LBFGS with EDIFFG= -0.15

I changed the EDIFFG in the INCAR file after the FIRE run, and then runned LBFGS.

Strangely the EDIFFG in the subdirecteries(01-0X) don't seem to change ...

Hi all:

I'm doing a CI-NEB calculation. I'm currently testing the calculation using different optimizers, one with the default GDIIS optimizer and one with L-BFGS.

In case the L-BFGS method fails to converge, is it reasonble to run CI-NEB with a more robust optimizer for several steps and continue ...