Search found 1882 matches

by graeme
Mon Dec 09, 2019 2:15 pm
Forum: VTSTTools
Topic: Vacancy migration frequency
Replies: 5
Views: 31

Re: Vacancy migration frequency

You are able to freeze atoms using the selective dynamics tags. Keep those same setting for the dynamical matrix calculation.
by graeme
Sun Dec 08, 2019 5:41 pm
Forum: VTSTTools
Topic: Vacancy migration frequency
Replies: 5
Views: 31

Re: Vacancy migration frequency

Within the harmonic approximation, you need to calculate the normal mode frequencies at the reactant and saddle point. Then the attempt frequency for hopping is given by: v = Prod v_rs / Prod v_ts , where Prod is the product of all the positive frequencies v = w/2pi, rs is the reactant state and ts ...
by graeme
Sat Dec 07, 2019 5:18 am
Forum: VTSTTools
Topic: VTST compilation
Replies: 3
Views: 41

Re: VTST compilation

No, you can only run the NEB using vasp. The CI-NEB and G-SSNEB are provided with the vtstcode.
by graeme
Fri Dec 06, 2019 9:43 pm
Forum: VTSTTools
Topic: VTST compilation
Replies: 3
Views: 41

Re: VTST compilation

Yes, you can run the NEB with the code built into vasp. The VTSTcode add a few features including the climbing image, double nudging, and optimizers which are more efficient for the NEB. There are also some print statements which are needed to work with the VTSTscripts.
by graeme
Fri Dec 06, 2019 8:49 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 6
Views: 134

Re: Bader Charge analysis

I would not recommend it. I would just use the standard Sb and Zn potentials. Zn, in particular, has plenty of valence electrons.
by graeme
Thu Dec 05, 2019 4:37 pm
Forum: eOn
Topic: how to submit job for eon with vasp
Replies: 3
Views: 956

Re: how to submit job for eon with vasp

If your linux cluster has a queueing system, you can submit a large number of jobs and let the queueing system run the jobs as the resources are free. Another useful tool, which is implemented in most queueing systems is an array job. Here is some information about that for the sge: https://arc.liv....
by graeme
Wed Dec 04, 2019 3:17 am
Forum: Bader
Topic: Bader Charge analysis
Replies: 6
Views: 134

Re: Bader Charge analysis

I suggest using the default values of NG(X,Y,Z)F and then increase them by 50% to check for convergence. If you are integrating the valence charge, you will not need a super-fine grid. The total number of electrons should be precisely correct, independent of the grid density - this is a property of ...
by graeme
Wed Dec 04, 2019 2:32 am
Forum: Bader
Topic: Bader Charge analysis
Replies: 6
Views: 134

Re: Bader Charge analysis

It is very important to do the Bader partitioning based upon the total charge and the integration based upon the valence charge. From the Bader analysis webpage: By adding the LAECHG=.TRUE. to the INCAR file, the core charge is written to AECCAR0 and the valance charge to AECCAR2. These two charge d...
by graeme
Wed Nov 27, 2019 7:43 pm
Forum: VTSTTools
Topic: NEB Settings for materials with complex potential energy surfaces.
Replies: 1
Views: 88

Re: NEB Settings for materials with complex potential energy surfaces.

I'm attaching an example ssneb calculation for the perovskite work that you mentioned. Any detailed questions should be directed to the primary author of that work, Penghao Xiao. Your second question is a little harder to answer. The NEB is a good method to find the reaction pathway and barrier for ...
by graeme
Tue Nov 26, 2019 12:23 am
Forum: VTSTTools
Topic: Problem in interpolation with nebmake.pl script
Replies: 12
Views: 287

Re: Problem in interpolation with nebmake.pl script

just the CHAIN+TOTAL
by graeme
Fri Nov 22, 2019 6:48 pm
Forum: Bader
Topic: Bader script is not responding while calculating Bader charge
Replies: 5
Views: 163

Re: Bader script is not responding while calculating Bader charge

It is a problem with vasp, but again, I don't know what causes it. It would be nice if the vasp developers would look into it.
by graeme
Fri Nov 22, 2019 6:34 pm
Forum: Bader
Topic: Bader script is not responding while calculating Bader charge
Replies: 5
Views: 163

Re: Bader script is not responding while calculating Bader charge

If you look in your AECCAR0 file, you will see that it is full of NaN (not a number) values. Vasp needs to output a proper AECCAR0 for the Bader analysis to work. I've seen this before but I'm not sure what causes it.
by graeme
Fri Nov 22, 2019 6:07 pm
Forum: Bader
Topic: Bader script is not responding while calculating Bader charge
Replies: 5
Views: 163

Re: Bader script is not responding while calculating Bader charge

If you can make the charge density files available to me, I'll run tests.
by graeme
Fri Nov 22, 2019 5:04 pm
Forum: VTSTTools
Topic: Problem in interpolation with nebmake.pl script
Replies: 12
Views: 287

Re: Problem in interpolation with nebmake.pl script

Oh, because the script finds the shortest path between the initial and final state (the minimum image convention). In your case, atom 1 goes across one side of the box to the other, as allowed by the periodic boundary conditions.