Dear Shivesh Sivakumar
You can do whatever you consider appropriate, as long as you discuss
it with all the details in the appropriate methods section of your
manuscripts. However, delocalization errors at not limited only to the
underestimation of the ionization potential and electron affinity
(i.e., of the band gap). Hence, the usage of HSE is recommended, but
the final choice depend on which property of your 2D materials are
inrerested in.
HTH
Giuseppe
Quoting Shivesh Sivakumar <[email protected]>:
Hello all,
I was performing a PBE calculation for a 2-D material and I found out the
bandstructure. However, since Kohn-Sham DFT underestimates bandgap, I
implemented the HSE functional to do an scf calculation and found out how
much my band gap has increased. Is it now possible for me to just manually
account for this adjustment in the bandstructure obtained from PBE ? I'm
curious because HSE calculations are turning out to be quite expensive
depending upon the density of mesh for the Fock operator.
To summarize, is it possible to shift the energy levels in my PBE
bandstructure to account for the bandgap increase I determined from the HSE
scf output? (Since HSE doesn't change the wavefunctions, and causes only a
rigid shift?)
Any insights would be much appreciated.
Best,
Shivesh Sivakumar
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
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I-00015 - Monterotondo Scalo (RM)
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E-mail: <[email protected]>
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