Hello dear colleagues and professors
Please what is the recommended type of pseudopotentials for QE? ultrasoft or norm conserving??
And from where get all types of pseudos (us, nc, pbe, pbesol,......)
Tanks in advance
PAW and Ultrasoft pseudopotentials are recommended for Quantum ESPRESSO. You can find these pseudopotentials at the following link: https://pseudopotentials.quantum-espresso.org/legacy_tables
Dear Hamza Elaamri ,
Quantum Espresso, per se, can handle different types of pseudopotentials, PAW, ultrasoft or Norm Conserving. However, some of its postprocessing analysis might be restricted to a given family of pseudopotentials. For example, optical properties are difficult to calculate with PAW or US. There is nothing magical here, this stems from the fact that nobody developed the code to do so. Also, if you plan to interface the output of QE with other codes (for example, Yambo) check their requirements first.
My general recommendation is however, to try to see how much your properties depend on the pseudopotentials. For example, the crystal lattices should not be too different.
In my experience, the SG15 NCs are quite solid and offer a good tradeoff between accuracy and numerical cost. They can be found here
http://www.quantum-simulation.org/potentials/sg15_oncv/
or on the website 'pseudodojo'.
Notice, however, not to mix the pseudopotential with the exchange correlation part. The PBE, PBESOL, and so on, define the exchange and correlation part of the Kohn-Sham potential. This part is, in PW, included in the pseudopotential. But, they correspond to different approximations with respect to the standard pseudopotential families. The pseudopotential is a way to describe the electrons that do not participate actively to the physical properties of the system.
I hope this helps,
Roberto
Pramod Gawal Thank you so much sir for your response
I will use them and compare
Roberto D'Agosta Thank you so much dear professor.
Your response is so helpful and clear. I appreciate it a lot.
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