Hi! Such "crowded" bands one sees also for film calculations. Comparing to 2D codes (e.g. FLEUR) I have seen that increasing vacuum clears the "crowded" high energy states.
Martin Gmitra Spintronics group Uni Regensburg, Germany On Mon, Jul 2, 2012 at 2:52 PM, Giovanni Cantele <giovanni.cantele at spin.cnr.it> wrote: > > On Jul 2, 2012, at 1:24 PM, ???? wrote: > > Hi! All > I'm trying to calculate the quantum conductance of quasi one dimension > structure with Wannier90 and PWscf. > But the one dimension band structure of suppercell is weird: bands with high > energy seem very "crowded". > I meet this problem when calculating Al nanowire and graphene nanoribbon. It > seems a computation error as > energy seems to be limitted in a small range. > I have raised the value of cutoff and distance between nanoribbons in > directions perpendicular to transport, > but results changed little. > My friend plots the bands of graphene nanoribbon with fplo, which can be a > reference I think. > > The input files and bands are in attachment. > > Thank you very much! > <nscf.in><scf.in><bands.jpg><bands_fplo.jpg>_______________________________________________ > > > It seems that your band structure is correct. If you want to look at higher > energy bands, due to the presence of > these "free-electron-like" states, you must increase nbnd. > > The Wannier90 procedure might be useful to single out bands with a specific > atomic character > (e.g. those deriving from the pz orbitals of C atoms). See, as an example, > Fig. 2 of Nano Lett., 2009, 9 (10), pp 3425?3429. > Giovanni > > > > > -- > > **** PLEASE NOTICE THE NEW E-MAIL ADDRESS: giovanni.cantele at spin.cnr.it > > Giovanni Cantele, PhD > CNR-SPIN > c/o Dipartimento di Scienze Fisiche > Universita' di Napoli "Federico II" > Complesso Universitario M. S. Angelo - Ed. 6 > Via Cintia, I-80126, Napoli, Italy > Phone: +39 081 676910 > Skype contact: giocan74 > > ResearcherID: http://www.researcherid.com/rid/A-1951-2009 > Web page: http://people.na.infn.it/~cantele > http://www.nanomat.unina.it > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum >