[Pw_forum] how to judge movement of HOMO and LUMO

[Rajdeep Banerjee]

Dear Prof. Marzari,
                           thank you very much for all your suggestions and
concerns. I'm really overwhelmed !
                           I've looked at work function calculation (thanks
to the links you provided). Now, I have a monolayer of crystalline
non-polar semiconductor material and I can calculate the planar and
macroscopic averages for unstrained and strained cases. But I'm still a
little bit confused about fixing the reference. Should I take macroscopic
average of Hartree potential at vacuum as the reference ?

I've thought about the following steps (in light of your previous
explanation):

1. Do a bulk calculation and find out the macroscopic average
2. Do the strained monolayer and see where the macroscopic average sits
with respect to vacuum level.
   But then I don't understand why do we need a bulk calculation if I can
get the vacuum level (in sigle-layer) and can align it for all strain cases
and refer the HOMO-LUMO directly to that !

                              I know I have a lot of doubts and I truly
appreciate your patience and all your helpful suggestions.

Thanks,
Rajdeep Banerjee
JNCASR
Bangalore, India
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20140605/c673c4a4/attachment.html>