Re: [Wien] Graphene bandstructure

Hi Prof Blaha, I have got the gap from plotting bandstructure as well as DOS calculations. I can see the linear dispersion at the K point just like the way it is suppose to be when I plot all the bands in eV range. But if I zoom in at the K point in meV range, I can see the gap. I

[Wien] Error in initialization stage

Hi, All: I met a problem in the initialization stage. I’m currently testing the effect of distance between clusters in nano wire calculation. When the distance is small (size of unit cell is small), everything is initialized properly. When I increase the distance until the size of unit cell is

Re: [Wien] Graphene bandstructure

The two eigenvalues at K must be identical by symmetry. If you have a splitting of some meV it means that your structure is slightly wrong. Typical errors: positions of 1/3 and 2/3 must be given in full precision. 0. is NOT 1/3 Am 22.12.2015 um 20:31 schrieb Islam, Md F: Hi Prof

Re: [Wien] Error in initialization stage

You are running out of memory. You cannot run 70x30x30 unit cells on a PC and in sequential mode. Am 22.12.2015 um 22:00 schrieb Hu, Wenhao: Hi, All: I met a problem in the initialization stage. I’m currently testing the effect of distance between clusters in nano wire calculation. When the

Re: [Wien] Graphene bandstructure

I think that RKmax (case.in1) is one of the important computational parameters in an accurate describing of the electronic structure of graphene. I think that RKmax equal to 8.0 leads to a better band structure result for graphene. All the best From: "Islam, Md F" To:

Re: [Wien] Graphene bandstructure

Thanks, for your reply. I have used a vacuum of 30 bohr but I can try with larger vacuum to check if it makes any difference. Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of

Re: [Wien] case.qtlup/dn files were empty

-BEGIN PGP SIGNED MESSAGE- Hash: SHA256 On 12/21/2015 06:51 PM, venkatesh chandragiri wrote: > I have done parallel SCF calculations in a cluster (the > case.vector_* files are created in a separate scratch folder) and > later I was copied the entire folder into a local computer due to >

[Wien] Graphene bandstructure

Hi, I am trying to do a bandstructure calculation of graphene to check if I can reproduce results discussed in literature (I am using a unit cell of 2 atoms). With spin-orbit coupling, there should be a gap of the order of few micro-eV and without spin-orbit, there should not be any gap at

Re: [Wien] Graphene bandstructure

Hi, For graphene, you need to add vacuum in the z-direction in order to avoid interactions between the periodically repeated monolayers. Maybe the vacuum that you used is not large enough. F. Tran On Tue, 22 Dec 2015, Islam, Md F wrote: Hi, I am trying to do a bandstructure calculation

Re: [Wien] Formula full-potential

Hi, I was wrong, since there is no detail on the construction of the potential in Dufek's thesis. To my knowledge, there is unfortunately no document where the construction of the potential is explained in great details specifically for WIEN2k. This is not trivial and made more complicated by

[Wien] wien2k workshop 2016

Dear WIEN2k users, We are happy to announce the WIEN2k workshop for 2016. It will be held at: McMaster University, Hamilton, Canada 4. - 7. June 2016 and hosted by O. Rubel (who contributed the BerryPI package to WIEN2k). The 23rd workshop in the history of

Re: [Wien] Graphene bandstructure

Graphene is metallic by "symmetry", i.e. EF is at a 2-fold eigenvalue at the K-point and bands cross with a linear dispersion. From where do you know that graphene has a gap in your calculations ?? From :gap in the scf file or from plotting the bandstructure or ... It the state at K is not

Re: [Wien] Graphene bandstructure

While I haven't done any graphene calculations, one of the typical issues in bandgap discrepancies is also the existence of strain. Ensure your lateral lattice parameters are optimized using your current functional so that you're certain you are looking at the band structure of the energetic

Re: [Wien] Graphene bandstructure

Hi Michael, Thanks for your comments. You may be right. I haven't relaxed lateral lattice parameters, just used the experimental values. Best regards, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at

Re: [Wien] Graphene bandstructure

Hi, Thanks for your suggestion. I have checked up to RKmax=9 but the gap didn't close. But I was using GGA xc functional. I will try with LDA if it makes any difference. I read in some paper, LDA is supposed to be used for these calculations. Regards, Fhokrul