[DFTB-Plus-User] comparison of HOMO and LUMO energy levels

[Bálint Aradi]

Dear Hongsheng,

> Dear DFTB+ users, I am doing some density of states calculations for
> none periodic systems with DFTB+ 18.2. I wonder whether I can compare
> the HOMO and LUMO energy levels for different structures to see the
> shift of HOMO and LUMO. Are the energy levels calculated by DFTB+ the
> absolute values? For some code based on plane wave basis set, like
> VASP, one cannot aline the HOMO and LUMO directly, because they are
> not  absolute values. Thank you very much.

For non-periodic systems, the levels should be comparable, as long as
you calculate them *without* periodic boundary conditions.

  Best regards,

  Bálint


-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/cms/people/b-aradi/


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://mailman.zfn.uni-bremen.de/pipermail/dftb-plus-user/attachments/20190617/78c38c39/attachment.sig>