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by graeme
Thu Dec 12, 2019 9:57 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 27
Views: 19346

Re: Bader Charge analysis

I don't know about the literature values. I don't see any problems with your calculation.
by graeme
Thu Dec 12, 2019 8:38 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 27
Views: 19346

Re: Bader Charge analysis

Not nessecarily. You can check convergence of the atomic charge values in the ACF.dat with respect to the grid density.
by graeme
Thu Dec 12, 2019 7:49 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 27
Views: 19346

Re: Bader Charge analysis

In my test I get the following output. Both the analysis and the ACF.dat report a total number of valence electrons of 136, which is expected for your system (12*8 for Zn and 5*8 for Sb). ----------- bader CHGCAR -ref CHGCAR_sum GRID BASED BADER ANALYSIS (Version 1.03 11/13/17) OPEN ... CHGCAR VASP5...
by graeme
Thu Dec 12, 2019 5:54 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 27
Views: 19346

Re: Bader Charge analysis

If you are using a command like: bader CHGCAR -ref CHGCAR_sum

then you should always get the correct total valence charge. Double check this with the -vac off flag.

If you do not see the total correct charge in the ACF.dat file, and you are willing to post the files here, I can take a look at it.
by graeme
Thu Dec 12, 2019 4:27 pm
Forum: Bader
Topic: Bader Charge analysis
Replies: 27
Views: 19346

Re: Bader Charge analysis

If you are analyzing the CHGCAR file, the sum of the valence charge will always be correct. Increasing the fft grid density can be used to check convergence of the Bader charges on each atom.
by graeme
Mon Dec 09, 2019 2:15 pm
Forum: VTSTTools
Topic: Vacancy migration frequency
Replies: 5
Views: 5962

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: 5962

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: 5609

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: 5609

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: 27
Views: 19346

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: 14579

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: 27
Views: 19346

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: 27
Views: 19346

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: 3317

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 ...