Re: [Wien] Energy convergence with spin-orbit
Thanks, prof Blaha. I was using TEMP broadening of 0.005 but I will try with a smaller number. Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Saturday, February 13, 2016 3:26 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Energy convergence with spin-orbit Convergence, in particular at surfaces and with localized states at EF, can be difficult. In particular, the default TETRA method might give problems due to the missing 3rd dimension and TEMP/TEMPS with some broadening (try as small as possible (0.002) first, but eventually you need to increase it a little. Also a too crude k-mesh can give problems and eventually you need to increase it. In any case, for a magnetocrystalline anisotropy usually huge k-meshes are necessary and careful testing is necessary, otherwise you get meaningless numbers. Am 12.02.2016 um 13:17 schrieb Islam, Md F: > Dear Wien2k users, > > I am trying to do a magnetic impurity calculation on a surface including > spin-orbit coupling. > I set the energy and charge convergence to 0.1 and 0.001, respectively. > The calculation is > well converged if magnetization is in-plane but for out of plane > magnetization it is not converging. > While charge satisfies convergence criterion very well, the energy keeps > oscillating near the 3rd/4th > decimal places.. I tried with different mixing (MSR1: 0.05 to 0.01) but > nothing seems to be working > for about 2 months. For larger mixing, job crashes with QTL-B error. I would > appreciate if you can > give me some suggestion to resolve the problem. > > I am also wondering if anyone has done any anisotropy calculation with > both self-consistent and > non self-consistent methods and whether they give the same anisotropy energy. > > > Thanks, > Fhokrul > > ___ > Wien mailing list > Wien@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 > -- -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.atWIEN2k: http://www.wien2k.at WWW: http://www.imc.tuwien.ac.at/staff/tc_group_e.php -- ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
[Wien] Energy convergence with spin-orbit
Dear Wien2k users, I am trying to do a magnetic impurity calculation on a surface including spin-orbit coupling. I set the energy and charge convergence to 0.1 and 0.001, respectively. The calculation is well converged if magnetization is in-plane but for out of plane magnetization it is not converging. While charge satisfies convergence criterion very well, the energy keeps oscillating near the 3rd/4th decimal places.. I tried with different mixing (MSR1: 0.05 to 0.01) but nothing seems to be working for about 2 months. For larger mixing, job crashes with QTL-B error. I would appreciate if you can give me some suggestion to resolve the problem. I am also wondering if anyone has done any anisotropy calculation with both self-consistent and non self-consistent methods and whether they give the same anisotropy energy. Thanks, Fhokrul ___ Wien mailing list Wien@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
Re: [Wien] Energy convergence with spin-orbit
Hi Prof. Marks, Thanks for your comments. The calculation is with single impurity, so there is no issue with FM or AFM alignment. I also chose the magnetization such that symmetry is not broken for in-plane or out-of-plane orientation. This particular calculation is done with Fe impurity but I have done the same set of calculations with Mn impurity on the same surface (Bi2Se3) without any problem. I agree that it doesn't guarantee a solution for all calculations but I just wanted to make sure I have explored all possibilities before give up on it. Here are some energies around which SCF is oscillating. :ENE : ** TOTAL ENERGY IN Ry = -2381169.79554107 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79537485 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79534902 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79494494 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79504374 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79510509 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79523383 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79548735 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79554582 This is going on for several weeks, so it doesn't look like converging slowly. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Laurence Marks [laurence.ma...@gmail.com] Sent: Friday, February 12, 2016 7:49 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Energy convergence with spin-orbit I have only done a few -so calculations, but from the list they seem to lead to problems. A few suggestions: a) Check for user error when you setup the in plane calculation. Have you used the right symmetry reduction? This seems to be the most common issue. b) Check that you are using the patches for issues in initso that have been posted. c) Look if your calculation is oscillating or just veery slowly converging. You can do a grep on some of the moments such as :ORB, :POM, :SPI in case.scf. I have seen these only slowly converge as the occupied states change. d) Think carefully about the physics of your problem. Some time ago I did a test LDA+U calculation for a Ni (metal) surface. It did not converge, which was OK. In Wien2k you are solving a fixed-point problem, and always assuming that such a solution exists. I do not believe that anything guaruntees that a solution exists in all cases. ( This is different from doing a variational calculation.) Maybe with your distances your impurities want to have an AFM ordering in-plane, but you are preventing this. These are just guesses, without more information it is hard to know. --- Professor Laurence Marks Department of Materials Science and Engineering Northwestern University http://www.numis.northwestern.edu Corrosion in 4D http://MURI4D.numis.northwestern.edu Co-Editor, Acta Cryst A "Research is to see what everybody else has seen, and to think what nobody else has thought" Albert Szent-Gyorgi On Feb 12, 2016 06:19, "Islam, Md F" <isl...@uta.edu<mailto:isl...@uta.edu>> wrote: Dear Wien2k users, I am trying to do a magnetic impurity calculation on a surface including spin-orbit coupling. I set the energy and charge convergence to 0.1 and 0.001, respectively. The calculation is well converged if magnetization is in-plane but for out of plane magnetization it is not converging. While charge satisfies convergence criterion very well, the energy keeps oscillating near the 3rd/4th decimal places.. I tried with different mixing (MSR1: 0.05 to 0.01) but nothing seems to be working for about 2 months. For larger mixing, job crashes with QTL-B error. I would appreciate if you can give me some suggestion to resolve the problem. I am also wondering if anyone has done any anisotropy calculation with both self-consistent and non self-consistent methods and whether they give the same anisotropy energy. Thanks, Fhokrul ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at<mailto:Wien@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 ___ Wien mailing list Wien@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
Re: [Wien] Energy convergence with spin-orbit
I have checked :ORB, :POM, :SPI as you suggested but case.scf doesn't seem to have any of those listed in it (doesn't return anything). I think :ORB works only if the calculation is done with LDA+U but my calculation is without U. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Laurence Marks [l-ma...@northwestern.edu] Sent: Friday, February 12, 2016 9:14 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Energy convergence with spin-orbit The energy is not always a good measure. Do, for instance if the impurity is atom 1, grep :POM001DN *scf Is this oscillating or slowly changing? Check the other terms I suggested. N.B., remember that you have periodic continuation in the surface plane, so unless you have a large supercell you are imposing FM ordering. On Fri, Feb 12, 2016 at 9:03 AM, Islam, Md F <isl...@uta.edu<mailto:isl...@uta.edu>> wrote: Hi Prof. Marks, Thanks for your comments. The calculation is with single impurity, so there is no issue with FM or AFM alignment. I also chose the magnetization such that symmetry is not broken for in-plane or out-of-plane orientation. This particular calculation is done with Fe impurity but I have done the same set of calculations with Mn impurity on the same surface (Bi2Se3) without any problem. I agree that it doesn't guarantee a solution for all calculations but I just wanted to make sure I have explored all possibilities before give up on it. Here are some energies around which SCF is oscillating. :ENE : ** TOTAL ENERGY IN Ry = -2381169.79554107 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79537485 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79534902 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79494494 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79504374 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79510509 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79523383 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79548735 :ENE : ** TOTAL ENERGY IN Ry = -2381169.79554582 This is going on for several weeks, so it doesn't look like converging slowly. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at<mailto:wien-boun...@zeus.theochem.tuwien.ac.at> [wien-boun...@zeus.theochem.tuwien.ac.at<mailto:wien-boun...@zeus.theochem.tuwien.ac.at>] On Behalf Of Laurence Marks [laurence.ma...@gmail.com<mailto:laurence.ma...@gmail.com>] Sent: Friday, February 12, 2016 7:49 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Energy convergence with spin-orbit I have only done a few -so calculations, but from the list they seem to lead to problems. A few suggestions: a) Check for user error when you setup the in plane calculation. Have you used the right symmetry reduction? This seems to be the most common issue. b) Check that you are using the patches for issues in initso that have been posted. c) Look if your calculation is oscillating or just veery slowly converging. You can do a grep on some of the moments such as :ORB, :POM, :SPI in case.scf. I have seen these only slowly converge as the occupied states change. d) Think carefully about the physics of your problem. Some time ago I did a test LDA+U calculation for a Ni (metal) surface. It did not converge, which was OK. In Wien2k you are solving a fixed-point problem, and always assuming that such a solution exists. I do not believe that anything guaruntees that a solution exists in all cases. ( This is different from doing a variational calculation.) Maybe with your distances your impurities want to have an AFM ordering in-plane, but you are preventing this. These are just guesses, without more information it is hard to know. --- Professor Laurence Marks Department of Materials Science and Engineering Northwestern University http://www.numis.northwestern.edu Corrosion in 4D http://MURI4D.numis.northwestern.edu Co-Editor, Acta Cryst A "Research is to see what everybody else has seen, and to think what nobody else has thought" Albert Szent-Gyorgi On Feb 12, 2016 06:19, "Islam, Md F" <isl...@uta.edu<mailto:isl...@uta.edu><mailto:isl...@uta.edu<mailto:isl...@uta.edu>>> wrote: Dear Wien2k users, I am trying to do a magnetic impurity calculation on a surface including spin-orbit coupling. I set the energy and charge convergence to 0.1 and 0.001, respectively. The calculation is well converged if magnetization is in-plane but for out of plane magnetization it is not converging. While charge satisfies convergence criterion very well, the energy keeps oscillating near the 3rd/4th decimal places.. I tried with different mixing (MSR1: 0.05 to 0.01) but nothing seems to be working for about 2 months. For larger mixing, job crashes with QTL-
Re: [Wien] Initialization with spin-orbit
Thanks, Prof. Blaha. Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Thursday, January 28, 2016 1:16 PM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Initialization with spin-orbit I can verify the problem. However, I could not find a fix quickly. Since I'm very busy in the next 2 weeks, it may take some time to debug this completely. As mentioned before, when SO does not change symmetry (you can see this in outsymso file if all operations are either type A or B), you can neglect symmetso. Am 28.01.2016 um 17:14 schrieb Islam, Md F: > Hi Prof. Blaha, > > Thanks for your reply. I have sent the structure to your email as you > have mentioned. > > Regards, > Fhokrul > > > From: wien-boun...@zeus.theochem.tuwien.ac.at > [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha > [pbl...@theochem.tuwien.ac.at] > Sent: Tuesday, January 26, 2016 5:11 PM > To: A Mailing list for WIEN2k users > Subject: Re: [Wien] Initialization with spin-orbit > > Not exactly sure what can cause the problem. > > Please search the mailing list, there was some time ago a patch for > symmetso. > > From your description of the problem (optimized/non-optimized > structure) it could be a symmetry problem, i.e. during optimization > (hexagonal case ???) the symmetry of the positions in the struct file > was slightly broken (rounding errors, something like 0.34 or > similar ...) > > Otherwise you have to send me your struct file. > > >> 1. Is it ok to initialize the job using initso with unrelaxed structure but >> after initialization, replace it by relaxed >> structure file and run the job? > > No, at least not in general as symmetso may/may not reduce symmetry > depending on the direction of magnetism. > > >> 2. For spin polarized calculations, spin-orbit may reduce the symmetry >> depending on the choice of magnetization >> direction. According to user guide, initso picks up correct symmetry >> for such cases. But if the system does not >> have any symmetry to begin with, then is it ok to initialize the >> structure treating as non-magnetic case? > > Yes, if you are already in P1 you are save and a further reduction of > symmetry is obviously not possible. Symmetso will not do anything. > > However,x kgen -so (or for P1: x kgen -fbz) is still necessary, as > for a non-so case, kgen will by default add inversion symmetry to P1, > which it should not do for a spin-polarized case. > > -- > -- > Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna > Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 > Email: bl...@theochem.tuwien.ac.atWIEN2k: http://www.wien2k.at > WWW: http://www.imc.tuwien.ac.at/staff/tc_group_e.php > -- > ___ > Wien mailing list > Wien@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 > ___ > Wien mailing list > Wien@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 > -- -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.atWIEN2k: http://www.wien2k.at WWW: http://www.imc.tuwien.ac.at/staff/tc_group_e.php -- ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
Re: [Wien] Initialization with spin-orbit
Hi Prof. Blaha, Thanks for your reply. I have sent the structure to your email as you have mentioned. Regards, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Tuesday, January 26, 2016 5:11 PM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Initialization with spin-orbit Not exactly sure what can cause the problem. Please search the mailing list, there was some time ago a patch for symmetso. From your description of the problem (optimized/non-optimized structure) it could be a symmetry problem, i.e. during optimization (hexagonal case ???) the symmetry of the positions in the struct file was slightly broken (rounding errors, something like 0.34 or similar ...) Otherwise you have to send me your struct file. > 1. Is it ok to initialize the job using initso with unrelaxed structure but > after initialization, replace it by relaxed > structure file and run the job? No, at least not in general as symmetso may/may not reduce symmetry depending on the direction of magnetism. > 2. For spin polarized calculations, spin-orbit may reduce the symmetry > depending on the choice of magnetization > direction. According to user guide, initso picks up correct symmetry for > such cases. But if the system does not > have any symmetry to begin with, then is it ok to initialize the > structure treating as non-magnetic case? Yes, if you are already in P1 you are save and a further reduction of symmetry is obviously not possible. Symmetso will not do anything. However,x kgen -so (or for P1: x kgen -fbz) is still necessary, as for a non-so case, kgen will by default add inversion symmetry to P1, which it should not do for a spin-polarized case. -- -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.atWIEN2k: http://www.wien2k.at WWW: http://www.imc.tuwien.ac.at/staff/tc_group_e.php -- ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
[Wien] Initialization with spin-orbit
Dear Wien2k users, I am having trouble with initializing a job with initso. I am doing a substitutional magnetic impurity calculation in a surface supercell (only 2 symmetry operations). After I relaxed the surface, I did an SCF calculation (more accurate) without spin-orbit which is converged well. But when I tried to do initialization with spin-orbit using initso, it gives following error message: forrtl: severe (64): input conversion error, unit 21, file /lunarc/nobackup/users/eishfh/WIEN2k/Bi2Se3/1Fe/1Fe/1Fe.struct_so Image PCRoutineLineSource symmetso 004B949A Unknown Unknown Unknown symmetso 004B7F96 Unknown Unknown Unknown symmetso 0048C400 Unknown Unknown Unknown symmetso 0047B1EF Unknown Unknown Unknown symmetso 0047A6F7 Unknown Unknown Unknown symmetso 004418E2 Unknown Unknown Unknown symmetso 0041BFCF rewr_ 23 rewr.f symmetso 0040627F MAIN__321 symmetso.f symmetso 0040374C Unknown Unknown Unknown libc.so.6 0030CEE1ED5D Unknown Unknown Unknown symmetso 00403649 Unknown Unknown Unknown 17.098u 57.124s 1:20.55 92.1% 0+0k 80+728808io 2pf+0w error: command /lunarc/nobackup/users/eishfh/SRC/Wien2k14.2-mpi/symmetso symmetso.def failed A new structure for SO calculations has been created (_so). If you commit it will create new 1Fe.struct, in1(c), in2c, inc, clmsum/up/dn, vspup/dn and vnsup/dn files. (Please SAVE any previous calculations) -- If I use the unrelaxed structure file, then initso does not give any error. So I suppose this error I am getting is related to the coordinates in the structure file of the relaxed geometry but I don't see anything wrong with the relaxed structure (after all, it works without spin-orbit). Could anyone suggests me how to fix the problem. On a related note, I have couple of questions: 1. Is it ok to initialize the job using initso with unrelaxed structure but after initialization, replace it by relaxed structure file and run the job? 2. For spin polarized calculations, spin-orbit may reduce the symmetry depending on the choice of magnetization direction. According to user guide, initso picks up correct symmetry for such cases. But if the system does not have any symmetry to begin with, then is it ok to initialize the structure treating as non-magnetic case? Thanks, Fhokrul ___ Wien mailing list Wien@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
Re: [Wien] Graphene bandstructure
Hi Xavier, Thanks for attaching the cif file. You are right that I didn't consider any particular symmetry. I just built the structure with the known lattice parameters from the literature. I thought if I have correct structure I would get correct SCF result even if I don't take advantage of all available symmetry, even though it takes more time. Anyway, I will try with this structure now. Best regards, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Xavier Rocquefelte [xavier.rocquefe...@univ-rennes1.fr] Sent: Wednesday, December 23, 2015 6:54 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Graphene bandstructure Dear Fhokrul Your structure looks strange to me. The angle is 60° and not 120° and it seems that you do not take benefit of the symetry. Here is a cif file of graphene based on the graphite structure in which I have simply increase the c parameter. The structure you are using may explain why you still have a gap (symetry problem). Best Regards Xavier #== # CRYSTAL DATA #-- data_VESTA_phase_1 _pd_phase_name 'C' _cell_length_a 2.45600 _cell_length_b 2.45600 _cell_length_c 15.0 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _symmetry_space_group_name_H-M 'P 63 m c' _symmetry_Int_Tables_number186 loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-y, x-y, z' '-x+y, -x, z' '-x, -y, z+1/2' 'y, -x+y, z+1/2' 'x-y, x, z+1/2' '-y, -x, z' '-x+y, y, z' 'x, x-y, z' 'y, x, z+1/2' 'x-y, -y, z+1/2' '-x, -x+y, z+1/2' loop_ _atom_site_label _atom_site_occupancy _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_adp_type _atom_site_B_iso_or_equiv _atom_site_type_symbol C1 1.0 0.00 0.00 0.00 Biso 1.00 C C2 1.0 0.33 0.67 0.00 Biso 1.00 C "Islam, Md F" <isl...@uta.edu> a écrit : > Sorry, in my earlier email, I meant to say with 30 x 30 x 1 mesh, gap > is smaller but > it doesn't close completely. > > Thanks, > Fhokrul > > > > From: wien-boun...@zeus.theochem.tuwien.ac.at > [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Islam, Md F > [isl...@uta.edu] > Sent: Wednesday, December 23, 2015 6:22 AM > To: A Mailing list for WIEN2k users > Subject: Re: [Wien] Graphene bandstructure > > Hi Prof Blaha, > > Here is the structure I am using. I tried to be as precise as > possible with position coordinates. > I think size of the vacuum is sufficiently large so that > supercell-supercell interaction is negligible. > So far what I have got is that with LDA xc if I use 25 x 25 x 1 > k-mesh there is a gap at the Fermi > level (which passes through K point) but if I use 30 x 30 x 1 k-mesh, > gap closes but DOS is not > zero at the Fermi level (about 0.001/eV). Please let me know if I am > doing anything wrong with > this calculation. > > > Thanks, > Fhokrul > > > Graphene > P LATTICE,NONEQUIV.ATOMS: 2 > MODE OF CALC=RELA unit=bohr > 4.647800 4.647800 30.00 90.00 90.00 60.00 > ATOM -1: X=0. Y=0. Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX:1.000 0.000 0.000 >0.000 1.000 0.000 >0.000 0.000 1.000 > ATOM -2: X=0.6667 Y=0.6667 Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX: 1.000 0.000 0.000 > 0.000 1.000 0.000 > 0.000 0.000 1.000 > 12 NUMBER OF SYMMETRY OPERATIONS > -1-1 0 0. > 0 1 0 0. > 0 0-1 0. > 1 > -1-1 0 0. > 0 1 0 0. > 0 0 1 0. > 2 > -1-1 0 0. > 1 0 0 0. > 0 0-1 0. > 3 > -1-1 0 0. > 1 0 0 0. > 0 0 1 0. > 4 > 0 1 0 0. > -1-1 0 0. > 0 0-1 0. > 5 > 0 1 0 0. > -1-1 0 0. > 0 0 1 0. > 6 > 0 1 0 0. > 1 0 0 0. > 0 0-1 0. > 7 > 0 1 0 0. > 1 0 0 0. > 0 0 1 0. > 8 > 1 0 0 0. > -1-1 0 0. > 0 0-1 0. > 9 > 1 0 0 0.0
Re: [Wien] Graphene bandstructure
Thank you very much for your suggestions/comments. a) I will create a new structure with H symmetry. b) I actually answered in one of my previous emails that I have calculated the gap from bandstructure. Using xmgrace I zoomed in on K point and found that there is a gap. I tried to use :GAP as you mentioned before but mesh size was probably not compatible with the pattern you mentioned, so I didn't get anything. Thanks again, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Wednesday, December 23, 2015 6:57 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Graphene bandstructure a) As expected, something is wrong with your structure. It should be a hexagonal lattice (H and not P) and the angle gamma should be 120 and not 60, and also the positions need to be changed then. With an "H" lattice, wien2k keeps the symmetry properly and is less affected by rounding errors. b) And secondly, you did not answer, how you got the "gap" (from scf-file, output1 or bandstructure or DOS ???) Forget DOS (there is a smearing parameter set by default !) when you use a H lattice and meshes which can be divided by 3 (because K has 1/3,1/3,0 coordinates and only with a mesh like 3 3 1, 6 6 1, 9 9 1, ... the "K"-point is in the mesh), you can use :GAP from scf, otherwise NOT. (best is to use a mesh conpatible with 2 and 3, so 6,6,1 or 12,12,1 ..., because this includes also the M point. On 12/23/2015 01:22 PM, Islam, Md F wrote: > Hi Prof Blaha, > > Here is the structure I am using. I tried to be as precise as possible > with position coordinates. > I think size of the vacuum is sufficiently large so that supercell-supercell > interaction is negligible. > So far what I have got is that with LDA xc if I use 25 x 25 x 1 k-mesh there > is a gap at the Fermi > level (which passes through K point) but if I use 30 x 30 x 1 k-mesh, gap > closes but DOS is not > zero at the Fermi level (about 0.001/eV). Please let me know if I am doing > anything wrong with > this calculation. > > > Thanks, > Fhokrul > > > Graphene > P LATTICE,NONEQUIV.ATOMS: 2 > MODE OF CALC=RELA unit=bohr > 4.647800 4.647800 30.00 90.00 90.00 60.00 > ATOM -1: X=0. Y=0. Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX:1.000 0.000 0.000 > 0.000 1.000 0.000 > 0.000 0.000 1.000 > ATOM -2: X=0.6667 Y=0.6667 Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX: 1.000 0.000 0.000 > 0.000 1.000 0.000 > 0.000 0.000 1.000 > 12 NUMBER OF SYMMETRY OPERATIONS > -1-1 0 0. > 0 1 0 0. > 0 0-1 0. > 1 > -1-1 0 0. > 0 1 0 0. > 0 0 1 0. > 2 > -1-1 0 0. > 1 0 0 0. > 0 0-1 0. > 3 > -1-1 0 0. > 1 0 0 0. > 0 0 1 0. > 4 > 0 1 0 0. > -1-1 0 0. > 0 0-1 0. > 5 > 0 1 0 0. > -1-1 0 0. > 0 0 1 0. > 6 > 0 1 0 0. > 1 0 0 0. > 0 0-1 0. > 7 > 0 1 0 0. > 1 0 0 0. > 0 0 1 0. > 8 > 1 0 0 0. > -1-1 0 0. > 0 0-1 0. > 9 > 1 0 0 0. > -1-1 0 0. > 0 0 1 0. > 10 > 1 0 0 0. > 0 1 0 0. > 0 0-1 0. > 11 > 1 0 0 0. > 0 1 0 0. > 0 0 1 0. > 12 > > > > > > From: wien-boun...@zeus.theochem.tuwien.ac.at > [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha > [pbl...@theochem.tuwien.ac.at] > Sent: Tuesday, December 22, 2015 3:29 PM > To: A Mailing list for WIEN2k users > Subject: 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 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 >> suppos
Re: [Wien] Graphene bandstructure
It is multiple of 6 along a & b in case.in0 file. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Laurence Marks [laurence.ma...@gmail.com] Sent: Wednesday, December 23, 2015 7:04 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Graphene bandstructure As a small addendum, you may also need to ensure that the fft size in lapw0 (via case.in0) is a multiple of 6 along a & b to preserve equivalence of atoms. --- Professor Laurence Marks Department of Materials Science and Engineering Northwestern University http://www.numis.northwestern.edu Corrosion in 4D http://MURI4D.numis.northwestern.edu Co-Editor, Acta Cryst A "Research is to see what everybody else has seen, and to think what nobody else has thought" Albert Szent-Gyorgi On Dec 23, 2015 06:57, "Peter Blaha" <pbl...@theochem.tuwien.ac.at<mailto:pbl...@theochem.tuwien.ac.at>> wrote: a) As expected, something is wrong with your structure. It should be a hexagonal lattice (H and not P) and the angle gamma should be 120 and not 60, and also the positions need to be changed then. With an "H" lattice, wien2k keeps the symmetry properly and is less affected by rounding errors. b) And secondly, you did not answer, how you got the "gap" (from scf-file, output1 or bandstructure or DOS ???) Forget DOS (there is a smearing parameter set by default !) when you use a H lattice and meshes which can be divided by 3 (because K has 1/3,1/3,0 coordinates and only with a mesh like 3 3 1, 6 6 1, 9 9 1, ... the "K"-point is in the mesh), you can use :GAP from scf, otherwise NOT. (best is to use a mesh conpatible with 2 and 3, so 6,6,1 or 12,12,1 ..., because this includes also the M point. On 12/23/2015 01:22 PM, Islam, Md F wrote: > Hi Prof Blaha, > > Here is the structure I am using. I tried to be as precise as possible > with position coordinates. > I think size of the vacuum is sufficiently large so that supercell-supercell > interaction is negligible. > So far what I have got is that with LDA xc if I use 25 x 25 x 1 k-mesh there > is a gap at the Fermi > level (which passes through K point) but if I use 30 x 30 x 1 k-mesh, gap > closes but DOS is not > zero at the Fermi level (about 0.001/eV). Please let me know if I am doing > anything wrong with > this calculation. > > > Thanks, > Fhokrul > > > Graphene > P LATTICE,NONEQUIV.ATOMS: 2 > MODE OF CALC=RELA unit=bohr > 4.647800 4.647800 30.00 90.00 90.00 60.00 > ATOM -1: X=0. Y=0. Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX:1.000 0.000 0.000 > 0.000 1.000 0.000 > 0.000 0.000 1.000 > ATOM -2: X=0.6667 Y=0.6667 Z=0.5000 > MULT= 1 ISPLIT= 8 > C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 > LOCAL ROT MATRIX: 1.000 0.000 0.000 > 0.000 1.000 0.000 > 0.000 0.000 1.000 > 12 NUMBER OF SYMMETRY OPERATIONS > -1-1 0 0. > 0 1 0 0. > 0 0-1 0. > 1 > -1-1 0 0. > 0 1 0 0. > 0 0 1 0. > 2 > -1-1 0 0. > 1 0 0 0. > 0 0-1 0. > 3 > -1-1 0 0. > 1 0 0 0. > 0 0 1 0. > 4 > 0 1 0 0. > -1-1 0 0. > 0 0-1 0. > 5 > 0 1 0 0. > -1-1 0 0. > 0 0 1 0. > 6 > 0 1 0 0. > 1 0 0 0. > 0 0-1 0. > 7 > 0 1 0 0. > 1 0 0 0. > 0 0 1 0. > 8 > 1 0 0 0. > -1-1 0 0. > 0 0-1 0. > 9 > 1 0 0 0. > -1-1 0 0. > 0 0 1 0. > 10 > 1 0 0 0. > 0 1 0 0. > 0 0-1 0. > 11 > 1 0 0 0. > 0 1 0 0. > 0 0 1 0. > 12 > > > > > > From: > wien-boun...@zeus.theochem.tuwien.ac.at<mailto:wien-boun...@zeus.theochem.tuwien.ac.at> > > [wien-boun...@zeus.theochem.tuwien.ac.at<mailto:wien-boun...@zeus.theochem.tuwien.ac.at>] > On Behalf Of Peter Blaha > [pbl...@theochem.tuwien.ac.at<mailto:pbl...@theochem.tuwien.ac.at>] > Sent: Tuesday, December 22, 2015 3:29 PM > To: A Mailing list for WIEN2k users > Subject: 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 wro
Re: [Wien] Graphene bandstructure
Hi Prof Blaha, Here is the structure I am using. I tried to be as precise as possible with position coordinates. I think size of the vacuum is sufficiently large so that supercell-supercell interaction is negligible. So far what I have got is that with LDA xc if I use 25 x 25 x 1 k-mesh there is a gap at the Fermi level (which passes through K point) but if I use 30 x 30 x 1 k-mesh, gap closes but DOS is not zero at the Fermi level (about 0.001/eV). Please let me know if I am doing anything wrong with this calculation. Thanks, Fhokrul Graphene P LATTICE,NONEQUIV.ATOMS: 2 MODE OF CALC=RELA unit=bohr 4.647800 4.647800 30.00 90.00 90.00 60.00 ATOM -1: X=0. Y=0. Z=0.5000 MULT= 1 ISPLIT= 8 C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 LOCAL ROT MATRIX:1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 1.000 ATOM -2: X=0.6667 Y=0.6667 Z=0.5000 MULT= 1 ISPLIT= 8 C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 LOCAL ROT MATRIX: 1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 1.000 12 NUMBER OF SYMMETRY OPERATIONS -1-1 0 0. 0 1 0 0. 0 0-1 0. 1 -1-1 0 0. 0 1 0 0. 0 0 1 0. 2 -1-1 0 0. 1 0 0 0. 0 0-1 0. 3 -1-1 0 0. 1 0 0 0. 0 0 1 0. 4 0 1 0 0. -1-1 0 0. 0 0-1 0. 5 0 1 0 0. -1-1 0 0. 0 0 1 0. 6 0 1 0 0. 1 0 0 0. 0 0-1 0. 7 0 1 0 0. 1 0 0 0. 0 0 1 0. 8 1 0 0 0. -1-1 0 0. 0 0-1 0. 9 1 0 0 0. -1-1 0 0. 0 0 1 0. 10 1 0 0 0. 0 1 0 0. 0 0-1 0. 11 1 0 0 0. 0 1 0 0. 0 0 1 0. 12 From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Tuesday, December 22, 2015 3:29 PM To: A Mailing list for WIEN2k users Subject: 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 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 don't think there is anything wrong with the structure. I did check all > bond lengths, > angles before I ran the calculations and they are correct. I suspect I may > have to adjust > parameters. I started to see some difference with LDA xc functional with > larger k mesh. > > > Thanks, > Fhokrul > > > > > > From: wien-boun...@zeus.theochem.tuwien.ac.at > [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha > [pbl...@theochem.tuwien.ac.at] > Sent: Tuesday, December 22, 2015 11:35 AM > To: A Mailing list for WIEN2k users > Subject: 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 degenerate, you have the wrong symmetry and are > not doing graphene. > > Am 22.12.2015 um 16:51 schrieb Islam, Md F: >> 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 Dirac point. But I am >> getting a gap of meV even without spin-orbit. I tried both GGA and LDA with >> very dense mesh but the gap does not close. So I am wondering if anyone >> have any suggestion about how to do it in Wien2k. >> >> >> Thanks, >> Fhokrul >> ___ >> Wien mailing list >> Wien@zeus.theochem.tuwien.ac.at >> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien >> SEARCH the MAILING-LIST at:
Re: [Wien] Graphene bandstructure
Sorry, in my earlier email, I meant to say with 30 x 30 x 1 mesh, gap is smaller but it doesn't close completely. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Islam, Md F [isl...@uta.edu] Sent: Wednesday, December 23, 2015 6:22 AM To: A Mailing list for WIEN2k users Subject: Re: [Wien] Graphene bandstructure Hi Prof Blaha, Here is the structure I am using. I tried to be as precise as possible with position coordinates. I think size of the vacuum is sufficiently large so that supercell-supercell interaction is negligible. So far what I have got is that with LDA xc if I use 25 x 25 x 1 k-mesh there is a gap at the Fermi level (which passes through K point) but if I use 30 x 30 x 1 k-mesh, gap closes but DOS is not zero at the Fermi level (about 0.001/eV). Please let me know if I am doing anything wrong with this calculation. Thanks, Fhokrul Graphene P LATTICE,NONEQUIV.ATOMS: 2 MODE OF CALC=RELA unit=bohr 4.647800 4.647800 30.00 90.00 90.00 60.00 ATOM -1: X=0. Y=0. Z=0.5000 MULT= 1 ISPLIT= 8 C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 LOCAL ROT MATRIX:1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 1.000 ATOM -2: X=0.6667 Y=0.6667 Z=0.5000 MULT= 1 ISPLIT= 8 C NPT= 781 R0=0.0001 RMT= 1.3200 Z: 6.0 LOCAL ROT MATRIX: 1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 1.000 12 NUMBER OF SYMMETRY OPERATIONS -1-1 0 0. 0 1 0 0. 0 0-1 0. 1 -1-1 0 0. 0 1 0 0. 0 0 1 0. 2 -1-1 0 0. 1 0 0 0. 0 0-1 0. 3 -1-1 0 0. 1 0 0 0. 0 0 1 0. 4 0 1 0 0. -1-1 0 0. 0 0-1 0. 5 0 1 0 0. -1-1 0 0. 0 0 1 0. 6 0 1 0 0. 1 0 0 0. 0 0-1 0. 7 0 1 0 0. 1 0 0 0. 0 0 1 0. 8 1 0 0 0. -1-1 0 0. 0 0-1 0. 9 1 0 0 0. -1-1 0 0. 0 0 1 0. 10 1 0 0 0. 0 1 0 0. 0 0-1 0. 11 1 0 0 0. 0 1 0 0. 0 0 1 0. 12 From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Tuesday, December 22, 2015 3:29 PM To: A Mailing list for WIEN2k users Subject: 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 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 don't think there is anything wrong with the structure. I did check all > bond lengths, > angles before I ran the calculations and they are correct. I suspect I may > have to adjust > parameters. I started to see some difference with LDA xc functional with > larger k mesh. > > > Thanks, > Fhokrul > > > > > > From: wien-boun...@zeus.theochem.tuwien.ac.at > [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha > [pbl...@theochem.tuwien.ac.at] > Sent: Tuesday, December 22, 2015 11:35 AM > To: A Mailing list for WIEN2k users > Subject: 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 degenerate, you have the wrong symmetry and are > not doing graphene. > > Am 22.12.2015 um 16:51 schrieb Islam, Md F: >> 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 Dirac point. But I am >> getting a gap of meV even without spin
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 don't think there is anything wrong with the structure. I did check all bond lengths, angles before I ran the calculations and they are correct. I suspect I may have to adjust parameters. I started to see some difference with LDA xc functional with larger k mesh. Thanks, Fhokrul From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha [pbl...@theochem.tuwien.ac.at] Sent: Tuesday, December 22, 2015 11:35 AM To: A Mailing list for WIEN2k users Subject: 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 degenerate, you have the wrong symmetry and are not doing graphene. Am 22.12.2015 um 16:51 schrieb Islam, Md F: > 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 Dirac point. But I am > getting a gap of meV even without spin-orbit. I tried both GGA and LDA with > very dense mesh but the gap does not close. So I am wondering if anyone > have any suggestion about how to do it in Wien2k. > > > Thanks, > Fhokrul > ___ > Wien mailing list > Wien@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 > -- -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.atWIEN2k: http://www.wien2k.at WWW: http://www.imc.tuwien.ac.at/staff/tc_group_e.php -- ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
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 t...@theochem.tuwien.ac.at [t...@theochem.tuwien.ac.at] Sent: Tuesday, December 22, 2015 10:20 AM To: A Mailing list for WIEN2k users Subject: 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 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 Dirac point. But I am > getting a gap of meV even without spin-orbit. I tried both GGA and LDA with > very dense mesh but the gap does not close. So I am wondering if anyone > have any suggestion about how to do it in Wien2k. > > > Thanks, > Fhokrul > ___ > Wien mailing list > Wien@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 > ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
[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 Dirac point. But I am getting a gap of meV even without spin-orbit. I tried both GGA and LDA with very dense mesh but the gap does not close. So I am wondering if anyone have any suggestion about how to do it in Wien2k. Thanks, Fhokrul ___ Wien mailing list Wien@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
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 [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Michael Sluydts [michael.sluy...@ugent.be] Sent: Tuesday, December 22, 2015 11:10 AM To: A Mailing list for WIEN2k users Subject: 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 minimum. Of course don't optimize the vacuum or you'll end up with graphite... Best regards, Michael Sluydts Op 22/12/2015 om 17:43 schreef Islam, Md F: > 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 > t...@theochem.tuwien.ac.at [t...@theochem.tuwien.ac.at] > Sent: Tuesday, December 22, 2015 10:20 AM > To: A Mailing list for WIEN2k users > Subject: 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 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 Dirac point. But I am >> getting a gap of meV even without spin-orbit. I tried both GGA and LDA with >> very dense mesh but the gap does not close. So I am wondering if anyone >> have any suggestion about how to do it in Wien2k. >> >> >> Thanks, >> Fhokrul >> ___ >> Wien mailing list >> Wien@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 >> > ___ > Wien mailing list > Wien@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 > ___ > Wien mailing list > Wien@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 -- ir. Michael Sluydts Center for Molecular Modeling Ghent University Technologiepark 903 9052 Zwijnaarde, Belgium tel. +32 (0)9 264 66 19 https://molmod.ugent.be ___ Wien mailing list Wien@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 ___ Wien mailing list Wien@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
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 From: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Hajar Nejati [hajar.nejatip...@yahoo.com] Sent: Tuesday, December 22, 2015 11:46 AM To: A Mailing list for WIEN2k users Subject: 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" <isl...@uta.edu> To: A Mailing list for WIEN2k users <wien@zeus.theochem.tuwien.ac.at> Sent: Tuesday, December 22, 2015 7:21 PM Subject: [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 Dirac point. But I am getting a gap of meV even without spin-orbit. I tried both GGA and LDA with very dense mesh but the gap does not close. So I am wondering if anyone have any suggestion about how to do it in Wien2k. Thanks, Fhokrul ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at<mailto:Wien@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 ___ Wien mailing list Wien@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
[Wien] changing occupancy of an orbital
Dear wien2k user, I understand there is a default case.inst file for each element in periodic table, for instance the case.inst file of tungsten has four 5d electrons and two 6s electrons. But if I like to change it to five 5d electrons and one 6s electron, is it possible to do that in wine2k? If so I am wondering if anyone can tell me how to change the occupancy of an orbital in case.inst file. I suppose just changing the numbers in case.inst file won't do any good. Thanks, Fhokrul -- next part -- A non-text attachment was scrubbed... Name: not available Type: application/ms-tnef Size: 3029 bytes Desc: not available Url : http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20081017/14f20da7/attachment.bin
[Wien] LDA+U for 5f electron system
Dear wien2k user, I am trying to apply LDA+U (SIC) method to obtain the ground state energy of a 5f electron system with an anti-ferromagnetic arrangement. For lower values of U, say 1eV or 1.5 eV, scf cycle does converge but if I use U = 3eV or 2.5 eV, some of the data points do not converge even after running few hundred cycles, making it difficult to find lowest energy configuration. I am wondering if anyone else have faced similar non-convergence problem with LDA+U method. Any comment will be appreciated. Thanks, Fhokrul -- next part -- An HTML attachment was scrubbed... URL: http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20080920/62593f6d/attachment.html
