UT theoretical chemistry code forum

Well, as you say, many of these questions are scientific in nature rather than technical. I can, however, try to answer some of the technical points. First, I would have no expectation of the energy going up or down when you include the implicit solvation model. It is certainly strange to have a tra...

That is a good question/comment. TSASE has code for solid-solid phase transitions, using any ASE calculator including LAMMPS and VASP. For concerted phase transitions, cell changes are essential. We have also studied solid-solid phase transitions using EON, but in that case, it is entirely modeled b...

First, I want to clarify that IDPP path will formally be different from the linear path. The issue is that we have a default fmax convergence criterion for the IDPP method so that if the bond lengths roughly change linearly in the linear path, the IDPP method can converge without changing the path. ...

I'm not sure that the error message accurately reflects the problem. The key issues that I see from your files is that you need to do an NEB calculation and run nebresults.pl before running neb2dim.pl. The neb2dim.pl script needs to read the energies of the images and the interpolated extrema in ord...

This may be a problem with the documentation; we do not have support for cell relaxation in EON.

Ok, I've looked into this and the IDPP force is lower than the default convergence of 0.05 eV/Ang even with the initial linear path. If I lower that convergence force, the IDPP path changes a bit, but not significantly. I think it is all working properly.

I will take a closer look tomorrow, but my guess is that the linear interpolation is a minimum for the IDPP method.

Yes, those are on the bottom face and being duplicated on the top face before relaxation.

I expect that atoms that are precisely on the boundary (such as the yellow atom on the corners) are shown on all of the corners. If that atom relaxes, it will only be shown in one location (top-right) instead of on all 8 corners.

That is more of a scientific question rather than a technical one. The nice thing about a constant volume is that you benefit from cancelation of errors in terms of the plane wave basis and kpoint sampling. However, when changes in the cell volume are important, then they should be considered.

Check that the settings on the endpoints are the same as the band. You will (almost certainly) find that they are different. Note: I put OUTCAR files in 00 and 08, which need to be consistent with the settings of your NEB calculation.

Yes, you will save computer time starting with cheaper settings. You will also get a sense of the uncertainty and importance of parameters when you make them more accurate. The IBRION=3 POTIM=0.1 setting is nice and safe but also pretty inefficient. You can switch to IBRION=1 to save time, especiall...

So I will almost always recommend using cheaper setting to find minima and saddles. You can always easily reconverge them with more precise settings. If you look at other questions on this forum, you can see many examples where people struggle getting convergence just because they focus all their ef...

Check if you have attached the files - they would help me see what's going on.

Has this issue been resolved, or is there still a problem using EON in mpi mode?