Random GUI search suggestions

NOMAD and FAIRmat
1

I was playing with the upstream nomad GUI search, to see if there is enough data for some thesis machine learning ideas and I have some usability suggestions. This is not really a bug so just posting random thoughts about the different search categories which I explored.

  • Elements/formula search: I really like this, this is a huge improvement from pre v1 I can’t think of anything more needed.
  • Structure: also very good, seems a bit limited by the normalizer system site limit at least on my datasets (and I wonder if matid could be able to detect for example structures with vacancies, etc… but that is not NOMAD related)
  • DFT: most of the search criteria are very useful but some seems fringe at best (exact exchange fraction)
    • I really miss here spinpolarization checkbox (select only spinpolarized, select only non-spinpolarized calculations)
    • For example the U value search looks OK, but the criterion of exact U value might be too specific, example if I would want to search for everything that does not use Hubbard correction, selecting min 0 and max 0 doesn’t work. Also how is it supposed to work if different atoms have different +U values?
    • I could use a dispersion correction treatment (van_der_waals_method) search

In general it seems problematic to search for a negative criteria. Like for example find me anything that has no +U as mentioned above (it looks like that is is often not possible to distinguish between there is no +U and there is no parser support to recognize if there is +U, few other search options have similar problem, e.g., Relativity Method: not able to distinguish none vs unknown…)

Workflow search

  • Molecular dynamics: looks OK, can’t think of anything needed there.
  • Geometry optimizations:
    • the histograms doesn’t seem useful at all (all it takes is one calculation with too big value to have everything in the first column), maybe x log axis could help?
    • search for “Final Force Maximum” in newtons is just plain annoying, there should be a unit selection, so one can search in some common units (eV/angstrom, Ry/Bohr, Ha/Bohr), etc.
    • I could use distinguishing between just atomic optimization and full cell optimization (including lattice parameters), for the latter case also a “Final stress maximum” criterion would be cool.

Another useful criterion (for example when searching for stuff that could be used to train a force field) would be to select calculations where stress or forces are calculated. Right now one can select geometry optimization or molecular dynamics where forces are guaranteed but I did not figure out how to select for example only single_point calculations that have forces (like the ones used for phonons), or stress. This could go somewhere in properties, but dunno where exactly. I believe this was supported pre-v1.

Yeah, but I don’t want to criticize too much, I’m really happy with the current NOMAD Archive (and Oasis) state and its very useful to me in general.

2

Dear @Pavel_Ondracka,

This feedback is very beneficial, and I can try to answer to some of the notes:

  1. and I wonder if matid could be able to detect for example structures with vacancies, etc… but that is not NOMAD related:

    We are actually working on something in this direction, but this will take some time to get right.

  2. In general it seems problematic to search for a negative criteria.

    What we are lacking is a way to construct queries using boolean logic. The API in principle does allow you to do it, but we don’t have a concept and implementation for this in the GUI where you work with mouse and keyboard. This is something that is in our backlog.

  3. the histograms doesn’t seem useful at all (all it takes is one calculation with too big value to have everything in the first column), maybe x log axis could help?

    Yes we have a bit of problem with outliers that mess up the statistics… We have played around with an idea that would filter out such outliers from the statistics by using some heuristics, but this is not yet implemented. What might help in the meantime is to use enable the “zoom”-checkbox which will rescale the histograms to the search region.

  4. search for “Final Force Maximum” in newtons is just plain annoying

    You can change the force unit in the top-right unit selection dialog. Also in the search bar you can type in: results.properties.geometry_optimization.final_force_maximum > 1 eV/angstrom The search bar will understand most common units.

I think @ladinesa, and @JosePizarro can comment on the other simulation-related comments.

Once again this is very valuable feedback, and on some of these ideas we can make definitely make into new features.

3

Hi Pavel,

Thanks a lot for the comments. I am only going to briefly comment on:

  • For example the U value search looks OK, but the criterion of exact U value might be too specific, example if I would want to search for everything that does not use Hubbard correction, selecting min 0 and max 0 doesn’t work. Also how is it supposed to work if different atoms have different +U values?

First, I agree with you on the 0 cases, but @laurih already commented on that.

Then, for the different U values, I am facing a similar problem with Dynamical Mean-Field Theory (DMFT). And I have not an honest final answer for this, but rather than those cases are unsearchable (I think is not possible to query for a full matrix Umn), but still should be tagged as DFT+U. I can ask Nathan Daelmann, as while for DMFT you can still find the data, I am not 100% sure of DFT+U; I am pretty sure you still can, but maybe implies doing more complex queries :slight_smile: