[Pw_forum] how to judge movement of HOMO and LUMO

[Sclauzero Gabriele]

Dear Rajdeep Banerjee,

    the following paper

http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.101.046405

and related work in the Pasquarello group (EPFL) could also be of help to solve your problem.

Best,


GS


Dear all,
           I want to look at the movement of valence band maxima (VBM / HOMO) and conduction band minima (CBM/LUMO) of a semiconductor for different values of applied tensile strain. The problem is how to fix a reference point to look at such a movement?
1. I can put Fermi energy as reference ... but for a semiconductor it doesn't mean anything as long as its in the band gap
2. I can put VBM as Fermi level and take that as reference ... but then I won't see VBM movement
3. I can use mid-point between HOMO and LUMO ... but then both the band edges will shift by same amount
4. I can fix an arbitrary point in the band gap as reference and check the movement without any shift ... but I'm a bit sceptical about this chice though.

           Please advise. Thanks in advance.

warmest regards,
Rajdeep Banerjee
JNCASR
Bangalore, India
_______________________________________________
Pw_forum mailing list
Pw_forum at pwscf.org<mailto:Pw_forum at pwscf.org>
http://pwscf.org/mailman/listinfo/pw_forum


Dr. Gabriele Sclauzero
Materials Theory - ETHZ
ETH Zurich, HIT G 43.2
Wolfgang-Pauli-Str. 27
8093 Zürich, Switzerland

Phone +41 44 633 94 10
Fax +41 44 633 14 59
gabriele.sclauzero at mat.ethz.ch<mailto:gabriele.sclauzero at mat.ethz.ch>
www.theory.mat.ethz.ch