[Wien] case.klist_band for band structure calculation having R-3c spacegroup
Juan Manuel Perez Mato
wmppemam at lg.ehu.es
Mon May 16 11:26:24 CEST 2016
> El 16/5/2016, a las 8:50, saurabh singh <saurabhiitmandi at gmail.com> escribió:
>
> Thank you so much Peter BLAHA Sir for your valuable suggestion .
> I have another query, In the Bilbao crystallographic server the k-vector description is given in the two basis i.e. Primitive basis and Conventional basis . In the user manual of Wien2k section 7.5.3 page 120, ix,iy,iz, defines the k-vector, where x= ix/idv etc. We use cartesian coordinates in units of 2π/a, 2π/b, 2π/c for P,C,F and B cubic, tetragonalnand orthorhombic lattices, but internal coordinates for H and monoclinic/triclinic lattices.
> For rhombohedral there is no suggestion given.
> Since we need to select the k-point manually in the xcrysden for high symmetric k-point, therefore it is very important to choose the correct basis coordinate. therefore I would like to know that in general for Rhombohedral space group, which basis coordinate (Primitive or Conventional) given in the Bilbao server should be used for making the case.klist_band.
> I have two choice in xcrysden:
> 1. Primitive Brillouin zone: if I choose this option in xcrysden to select the k-point coordinate then should i use the primitive basis coordinate of high k-point from the Bilbao server.
> 2. Conventional Brillouin zone: for this should i use the conventional basis coordinate from the Bilbao server.
>
> Please give your suggestion for choosing the proper basis coordinate of k-point for rhmbohedral lattice from Bilbao server.
>
> On Sun, May 15, 2016 at 10:48 PM, saurabh singh <saurabhiitmandi at gmail.com <mailto:saurabhiitmandi at gmail.com>> wrote:
> Dear All Wien2k users,
>
> We want to calculate the band structure of LaCoO3 compound. The space group of this compound is R-3c (No. 167). In the Wien2k user manual, it is suggested for R lattice to use rhombohedral coordinates. Therefore we made the case.structure file using lattice parameters a=b= 10.2541 Bohr, c= 24.5494, alpha=beta=90 degree, gamma = 120 degree, and converted rhombohedral coordinates for each atom. When we try to make case.klist_band file by selecting the case.structure folder path in xcrysden, it says " the guessed bravais lattice type: not supported (the XSF's group number is 7). We tried the two different way to get the case.klist_band as follows:
>
> 1) Firstly, we have changed the lattice parameters in case.structure file in accordance to rhombohedral structure. We thought if the lattice parameters and atomic coordinate both will be accordance to rhombohedral then xcrysden can recognize the case.struct file. But again case.struct file does not recognized by xcrysden.
>
> 2) Secondly, we took the hcp.klist file given in wien2k SRC folder, which is as follows:
> GAMMA 0 0 0 40 2.0-0.5 1.5 Template for hcp structure
> 1 0 0 40 2.0
> 2 0 0 40 2.0
> 3 0 0 40 2.0
> 4 0 0 40 2.0
> 5 0 0 40 2.0
> 6 0 0 40 2.0
> 7 0 0 40 2.0
> 8 0 0 40 2.0
> 9 0 0 40 2.0
> SIGMA 10 0 0 40 2.0
> 11 0 0 40 2.0
> 12 0 0 40 2.0
> 13 0 0 40 2.0
> 14 0 0 40 2.0
> 15 0 0 40 2.0
> 16 0 0 40 2.0
> 17 0 0 40 2.0
> 18 0 0 40 2.0
> 19 0 0 40 2.0
> M 20 0 0 40 2.0
> 29 2 0 60 2.0
> 28 4 0 60 2.0
> 27 6 0 60 2.0
> 26 8 0 60 2.0
> 25 10 0 60 2.0
> 24 12 0 60 2.0
> 23 14 0 60 2.0
> 22 16 0 60 2.0
> 21 18 0 60 2.0
> K 20 20 0 60 2.0
> 19 19 0 60 2.0
> 18 18 0 60 2.0
> 17 17 0 60 2.0
> 16 16 0 60 2.0
> 15 15 0 60 2.0
> 14 14 0 60 2.0
> 13 13 0 60 2.0
> 12 12 0 60 2.0
> 11 11 0 60 2.0
> LAMBDA10 10 0 60 2.0
> 9 9 0 60 2.0
> 8 8 0 60 2.0
> 7 7 0 60 2.0
> 6 6 0 60 2.0
> 5 5 0 60 2.0
> 4 4 0 60 2.0
> 3 3 0 60 2.0
> 2 2 0 60 2.0
> 1 1 0 60 2.0
> GAMMA 0 0 0 60 2.0
> 0 0 1 20 2.0
> 0 0 2 20 2.0
> 0 0 3 20 2.0
> 0 0 4 20 2.0
> DELTA 0 0 5 20 2.0
> 0 0 6 20 2.0
> 0 0 7 20 2.0
> 0 0 8 20 2.0
> 0 0 9 20 2.0
> A 0 0 10 20 2.0
> END
>
> We renamed this hcp.klist file as case.klist_band and used it for band structure calculation. The calculated band structure gives the indirect band gap which is almost equal to the band gap obtained from SCF calculation.
>
> My question is, whether we can use the hcp.klist (given in Wien2k SRC folder) as case.klist_band for band structure calculation if the compound have R-3c space group and having the hexagonal lattice parameter and rhombohedral atomic coordinate in the case.struct file. Please let me know I am doing right or there is some different way to do it.
>
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
**************************************************
J. Manuel Perez-Mato
Fac. Ciencia y Tecnologia,
Universidad del Pais Vasco, UPV
48080 BILBAO,
Spain
tel. +34 946012473
fax. +34 946013500
***************************************************
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20160516/bcc3746a/attachment.html>
-------------- next part --------------
_______________________________________________
Wien mailing list
Wien at zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
More information about the Wien
mailing list