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by short_circut 4482 days ago
I actually use Quantum Espresso rather extensively in my own research. It should work quite well with an interface like this. It has a sub-program pp.x specifically designed to make common plots out of the programs output.

I can tell you that it tends to be a little slow compared to some other codes such as VASP, and it does tend to take up a good deal more disk space. It has a few other quirks but it is a great program. Also its wavefunctions can be exported to XML files.

If you are looking anytime soon for people with computational physics/chemistry specific knowledge I may be looking for work soon.
2 comments
Osmium 4482 days ago
> Also its wavefunctions can be exported to XML files.

Surely they'd be huge though? In any case, it's always interesting to hear experiences about other codes. I haven't actually used Quantum Espresso myself, but I know it's Free, so had been considering it... How would you quantify "a little slow"?

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short_circut 4482 days ago
The xml files can be huge, but wavefunction files in general tend to be. The main point being that it allows for direct access to the files for custom code work.

I can quantify a little slow with a specific research experience. This isn't the case for all uses of Quantum Espresso, etc....

When I run an HSE or PBE0 calculation on 192 atoms it takes just over 2 weeks of computation time using quantum espresso. When my co-worker did it in vasp using the same computing systems it took just a couple of days. I don't really know the reason for this.

From time to time things like this creep up.

One of the quirks you should be aware of an enforce in all runs where this is relevant is you need to set

wf_collect=.true.

if you do not then each subsequent run will require the same number of processors in the same configuration each time the program is run.

http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT...

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adw 4482 days ago
When I was working on this stuff, the most popular GPLed code was ABINIT – do people still use that? (My lab was a SIESTA shop, and there were a lot of CASTEP people around, but not many using VASP...)
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