[Pw_forum] functionals and pseudopotentials for bandgap.

[Eduardo Ariel Menendez Proupin]

Dear fellows,

I am swimming (but not diving yet) in the sea of hybrid functionals. I need
to estimate bandgap corrections of a crystal made of benzene-like
molecules. After some googling, I am almost at the same place, but looking
to the HSE functional, and I tested the HSE and the TPSS with the example
of silicon. I request a few advise, these are my dubts

1) Does the metaGGA functional TPSS improves the bandgap ?

2) What  pseudopotential (i.e. what functional) can be used for a
calculation with HSE?

3) What kind of pseudoptential are the CPBE*nlcc.RRKJ3 in   EXX_example

4) I would appreciate a recommendation of a published benchmark on the
performance of different functionals for the gap.

Thanks

-- 


Eduardo Menendez Proupin
Departamento de Química Fisica Aplicada
Facultad de Ciencias
Universidad Autónoma de Madrid
28049 Madrid, Spain
Phone: +34 91 497 6706

On leave from: Departamento de Fisica, Facultad de Ciencias, Universidad de
Chile URL: http://fisica.ciencias.uchile.cl/~emenendez

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