Add support for charge analysis about aiidalab-qe HOT 2 OPEN

I'll add some (hopefully useful) context from previous experience of partially succeeding at this with AiiDA-QE:

Charge density can be computed with a PpCalculation run, which is still supported in AiiDA-QE and one simply has to give the correct value for plot_num (e.g. plot_num = 0 for valence charge) and also for iflag and output_format. The parser for a PpCalculation should return the results in a JSON file. Last time I tried this, I decided to just download the cube files I generated from their working directories on the remote machine instead of using the JSON file since I wasn't sure how to convert JSON to cube format.

For Bader charges, I used the pre-compiled executable from Richard Bader's group website which worked directly in the terminal and accepts Gaussian cube files as input. It's possible that there are "fancier" Bader charge analysis programs out there, but this one should be transferable to different Linux/Mac systems and run quite efficiently (I clocked it at ~1 second for a 16 atom unit cell with 100 valence electrons).

The way I see it, this could be better integrated to AiiDA/AiiDALab if:

1. There is some way to convert JSON (or the ArrayData returned by the CalcJob node) to Gaussian cube format and get it to work in AiiDA.
2. The Bader executable can be made to work with AiiDA-Shell, or something similar.

Hope this helps.

from aiidalab-qe.

Thanks, @PNOGillespie, for the suggestion!

The bader charge calcjob, workchain and qeapp plugin are implemented in this repository. It uses bader code from Henkelman group. The cube file is used directly.

from aiidalab-qe.