fold2Bloch
> Hello All, > In regard to the ongoing discussion about band structure, I have a query > since I am newly working in this field of computational solid state > physics. > While calculating band structure, Is it absolutely necessary that I > calculate the band structure of a unit cell and not of a supercell? > If during structural relaxation I am using a supercell, will the > calculated > band structure of a supercell be the same as that of a unit cell band > structure in that case? How do I get the unit cell parameters from the > supercell relaxation output? Is there any code to extract the unit cell > data from the SIESTA output files for a supercell? > > Any hints in this regard is highly appreciated. > Thank you in advance. > > Sunetra Das > Dept. of Physics, > MMC College, > Kolkata, > India. > > On 6 July 2017 at 01:40, Ritwik Vatsyayan <ritwikvatsya...@gmail.com> > wrote: > >> Dear Aakanksha, >> I am using XCrysDen version 1.5.60. >> >> >> Regards, >> Ritwik >> >> On Mon, Jul 3, 2017 at 1:53 AM, AAKANKSHA SUD >> <aakankshasood0...@gmail.com >> > wrote: >> >>> Dear Ritwik >>> I am happy that my suggestions were helpful to you. I was just >>> wondering that how did you open .xyz file in xcrysden because such >>> files >>> cannot be opened in it. Perhaps you are using some other version.I >>> would >>> really appreciate if you could tell me that which version of xcrysden >>> are >>> you using that supports .xyz file. >>> >>> Thanks >>> Aakanksha >>> ------------------------------ >>> From: Ritwik Vatsyayan <ritwikvatsya...@gmail.com> >>> Sent: 7/3/2017 1:30 AM >>> >>> To: siesta-l@uam.es >>> Subject: Re: [SIESTA-L] Plotting Bandstructure in Siesta >>> >>> Dear Aakanksha, >>> Thank you so much for that tip. I was >>> normally using the .xyz file generated from siesta run after optimizing >>> the >>> geometry, but I guess that will not give the information about the >>> k-points. >>> I really appreciate your time and effort in this. >>> >>> Best Regards, >>> Ritwik >>> >>> On Sat, Jul 1, 2017 at 7:24 AM, AAKANKSHA SUD < >>> aakankshasood0...@gmail.com> wrote: >>> >>>> Hi ritwik >>>> Could you please elaborate the steps you followed. First you have to >>>> optimise the geometry . So after optimisation you will get .xv file. >>>> There >>>> is a utility in siesta xv2xsf . Use that to generate .xsf file.Now >>>> open >>>> that file in xcrysden and generate the kpoints. After that do the >>>> calculation for bandstructure. Hope it helps. >>>> >>>> Regards >>>> Aakanksha >>>> ------------------------------ >>>> From: Ritwik Vatsyayan <ritwikvatsya...@gmail.com> >>>> Sent: 7/1/2017 1:31 AM >>>> To: siesta-l@uam.es >>>> Subject: Re: [SIESTA-L] Plotting Bandstructure in Siesta >>>> >>>> Dear Aakanksha, >>>> Thank you for suggesting XCrysDen. I >>>> wanted to know that when you are using xcrysden to generate the >>>> k-points, >>>> what is the extension of the file you use as the input? I tried using >>>> the >>>> SystemLabel.xyz file, but it doesn't give me the option for making >>>> k-path. >>>> Is there some other file generated by Siesta which can be used? >>>> >>>> Regards, >>>> Ritwik Vatsyayan >>>> >>>> On Thu, Jun 29, 2017 at 1:59 AM, AAKANKSHA SUD < >>>> aakankshasood0...@gmail.com> wrote: >>>> >>>>> Hi Ritwik >>>>> It would be better if you use xcrysden to know the high symmetry pts. >>>>> And using xcrysden you can easily generate the kpoints based on the >>>>> brillouin zone.and its necessary to use a cyclic closed path. We are >>>>> defining a region of brilliouin zone and by repeating it we can >>>>> define >>>>> whole zone so its necessary to specify the cyclic path. And >>>>> specifying the >>>>> number of intersections between two k points is also necessary. >>>>> Regarding >>>>> the reciprocal lattice vectors or fractional it depends like in which >>>>> coordinates you are specifying the kpoints. I insist that you should >>>>> use >>>>> xcrysden or some other kpoint generating software . >>>>> >>>>> Hope it helps.. >>>>> >>>>> Regards >>>>> Aakanksha >>>>> ------------------------------ >>>>> From: Ritwik Vatsyayan <ritwikvatsya...@gmail.com> >>>>> Sent: 6/29/2017 1:32 AM >>>>> To: siesta-l@uam.es >>>>> Subject: [SIESTA-L] Plotting Bandstructure in Siesta >>>>> >>>>> Dear Siesta Users, >>>>> I am working on a system with a >>>>> hexagonal lattice, and I want to plot the bandstructure for the same. >>>>> I read online at: https://lampx.tugraz.at/~hadle >>>>> y/ss1/bzones/hexagonal.php >>>>> that the high symmetry points of the first Brillouin zone of a simple >>>>> hexagonal lattice are: >>>>> Γ: (0,0,0) >>>>> M: (1/2,0,0) >>>>> K: (2/3,1/3,0) >>>>> H: (2/3,1/3,1/2) >>>>> A: (0,0,1/2) >>>>> L: (1/2,0,1/2) >>>>> These points are in the fractional format. I want to plot the >>>>> bandstructure using these points. >>>>> In the fdf file, we must declare the BandLinesScale. For these >>>>> co-ordinates, would the format be : ReciprocalLatticeVectors or pi/a >>>>> ? >>>>> >>>>> Also, for plotting the bandstructure, do we need to make a cyclic >>>>> path, >>>>> for example, Γ->M->K->Γ ? Or can we stop at Γ->M->K as well? >>>>> >>>>> I would be grateful if anyone can help me out in this. Thank you for >>>>> your time. >>>>> Regards, >>>>> Ritwik Vatsyayan >>>>> Pre-Final Year Undergraduate >>>>> Electronics and Communication Engineering >>>>> Indian Institute of Technology, Guwahati >>>>> >>>> >>>> >>> >> > -- Prof. Sushil Auluck Phone:+91-512-6797092/6148 Department of Physics +91-512-6798177(Home) Indian Institute of Technology Cell :+91-9305548667 Kanpur 208016 (UP) Fax :+91-512-6790914 India E-mail:saul...@iitk.ac.in ...............................................:saul...@gmail.com http://www.nplindia.org/prof-sushil-auluck http://www.iitk.ac.in/phy/index.php/component/content/article/2-uncategorised/124-sushil-auluck http://www.iitk.ac.in/phy/People/phy_facvis.html http://www.iitk.ac.in/phy/New01/profile_SA.html http://www.iitk.ac.in/phy/index.php/people/faculty http://www.iitk.ac.in/phy/index.php/people/faculty/12-people/faculty/profile/88-sushil-auluck ....................................................................... ~
