[QE-users] Hubbard U Parameters in pmw.x

[Yin-Ying Ting]

Dear Quantum Espresso Community,

I am currently working with the poormanwannier.x (pmw.x) as demonstrated
in example05 of PP. In this example, the procedure begins with a
self-consistent field (SCF) calculation without the incorporation of
Wannier functions (wf) and with very small Hubbard parameters (around
0.001). This is followed by the execution of pmw.x and a subsequent
second SCF calculation, this time including Wannier functions and the
Hubbard U parameters.

My question pertains to the rationale behind this two-step SCF
calculation approach, particularly concerning the Hubbard U parameters.
Why is it not recommended or feasible to employ the Hubbard U parameters
right from the first SCF calculation? Understanding the underlying
reasoning for this process would greatly enhance my comprehension of the
method and its applications.

I appreciate any insights or explanations you can provide. Thank you for
your time and assistance.

Best regards,

PhD student in Forschungszentrum Jülich

Yin-Ying Ting

--

Forschungszentrum Jülich GmbH
Institute of Energy and Climate Research
Theory and Computation of Energy Materials (IEK-13)
E-mail: y.ting at fz-juelich.de



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Forschungszentrum Jülich GmbH
52425 Jülich
Sitz der Gesellschaft: Jülich
Eingetragen im Handelsregister des Amtsgerichts Düren Nr. HR B 3498
Vorsitzender des Aufsichtsrats: MinDir Stefan Müller
Geschäftsführung: Prof. Dr. Astrid Lambrecht (Vorsitzende),
Karsten Beneke (stellv. Vorsitzender), Dr. Ir. Pieter Jansens
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