From lanhaiping at gmail.com Tue Dec 5 19:20:48 2006 From: lanhaiping at gmail.com (lan haiping) Date: Wed, 6 Dec 2006 02:20:48 +0800 Subject: [Wannier] About Born Charge Message-ID: Dear Developers , I am wondering about born charge calculation by relative displacement Wannier centers. I tried to repeat this calculation for anatase TiO2 system. Since there are 6 atoms in unit cell, i just displace one of O sites about 0.1% of cell lattice along x direction. I then come to a problem about kpoint setting in 'nscf' calculation of the displacing case. With kmesh.sh scripts, i set 4x4x4 kmesh for 'nscf' calculation. When i tried to run pw2wannier90.x code, calculation failed due to different kpoints between result of 'nscf' calculation and wannier90 's kmesh setting. For my case , there are 64 kpoints i set for 'nscf' calculation.Due to symmetry , the number of kpoints output file gave is 164 kpoints. I think there must be some aspects of this calculation scheme i donot catch much, or understand wrong. Would you please give me some comments ? Regards. -- Hai-Ping Lan Department of Electronics , Peking University , Bejing, 100871 -------------- next part -------------- An HTML attachment was scrubbed... URL: From wierzbom at ts.infn.it Wed Dec 6 12:12:54 2006 From: wierzbom at ts.infn.it (Malgorzata Wierzbowska) Date: Wed, 6 Dec 2006 12:12:54 +0100 (CET) Subject: [Wannier] About Born Charge In-Reply-To: References: Message-ID: On Wed, 6 Dec 2006, lan haiping wrote: Hi, > Dear Developers , > > I am wondering about born charge calculation by relative displacement > Wannier centers. > I tried to repeat this calculation for anatase TiO2 system. Since there are > 6 atoms in unit cell, i just displace one of O sites about 0.1% of cell > lattice along x direction. I then come to a problem about kpoint setting in > 'nscf' calculation of the displacing case. > With kmesh.sh scripts, i set 4x4x4 kmesh for 'nscf' calculation. When i > tried to run pw2wannier90.x code, calculation failed due to different > kpoints between result of 'nscf' calculation and wannier90 's kmesh setting. The k-mesh in nscf for later use in wannier calculations has to be given in the whole Brillouin zone and it needs to be uniform. > For my case , there are 64 kpoints i set for 'nscf' calculation.Due to > symmetry , the number of kpoints output file gave is 164 kpoints. > I think there must be some aspects of this calculation scheme i donot catch > much, or understand wrong. Would you please give me some comments ? > You should not use the symmetry in this case. You cannot use the option "authomatic" k-point generation. Instead, in nscf, you should give the list of all k-points. I know this takes longer for the calculation but at this stage it is done like this because we had no time yet to do it better. About the number of k-points: It depends on how big is your cell in the reciprocal space. If you have some time, you could use 2*2*2=8 and 4*4*4=64 and 8*8*8=512 and tell us what is the difference at the end :-) If your cell is cubic you use number of k-points n1=n2=n3, if your cell is alongated you should find such grid with which the distances between k-points (in reciprocal space) are almost equal. Gosia From lanhaiping at gmail.com Mon Dec 18 01:52:23 2006 From: lanhaiping at gmail.com (lan haiping) Date: Mon, 18 Dec 2006 08:52:23 +0800 Subject: [Wannier] Question about final spreads Message-ID: Dear All, I came to confusion about final results of wannierise procedure. I am trying to analyse anatase tio2 wannier function and born charge with wannier90.x. I performed 2 calculations with 2 different projection functions sets, other settings are same. Both reached convergenc (error deltas for total Omega are about 1E-10). But the total spreads and wannier centers are quite different. For my first calculation, i just start with sp2 and pz functions at O sites, the total spreads finally obtained is 14.397. While for the second calculation, the projetion functions are s/px/py/pz functions at O sites, the total spreads finally obtained is then 15.2170. The wannier functions of second calculation could be classed into 4 groups by spreads , while the conclusion is not hold for the fist calculation ( the wannier functions are then classed into 8 groups ). According to MV paper, the MLWFs reflect structures' symmetry by spreads. So, Both 2 calculations are not correct. Would you please give me some comments ? And input files are below : *num_wann = 16 num_iter = 2000 guiding_centres = T exclude_bands = 1 2 3 4 5 6 7 8 25 26 27 28 29 30 begin projections O : sp2 O : pz end projections begin atoms_cart Ti 0.000000000 -0.000000000 0.000000000 Ti 0.000000000 1.892500000 2.378500000 O 0.000000000 0.000000000 1.979863400 O 0.000000000 -0.000000000 7.534136600 O 0.000000000 1.892500000 4.358363400 O 0.000000000 1.892500000 0.398636600 end atoms_cart* *begin unit_cell_cart Ang 1.8925 -1.8925 4.757 1.8925 1.8925 4.757 -1.8925 -1.8925 4.757 end unit_cell_cart mp_grid : 6 6 6 begin kpoints ...... end kpoints* two final spreads and wannier centers are attached. *Regards* Hai-Ping -- Hai-Ping Lan Department of Electronics , Peking University , Bejing, 100871 -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- Final State WF centre and spread 1 ( -0.057359, 0.368438, 2.144012 ) 0.81913203 WF centre and spread 2 ( -0.057359, -0.368438, 2.144012 ) 0.81913201 WF centre and spread 3 ( 0.207447, 0.000000, 1.889906 ) 1.06292459 WF centre and spread 4 ( -0.197679, 0.225730, 7.480939 ) 0.95045581 WF centre and spread 5 ( -0.197683, -0.225729, 7.480937 ) 0.95045348 WF centre and spread 6 ( 0.383935, 0.000000, 7.384053 ) 0.82485652 WF centre and spread 7 ( -0.197693, 2.118226, 4.411569 ) 0.95044526 WF centre and spread 8 ( -0.197669, 1.666767, 4.411555 ) 0.95046140 WF centre and spread 9 ( 0.383935, 1.892503, 4.508447 ) 0.82485530 WF centre and spread 10 ( -0.057359, 2.260938, 0.234488 ) 0.81913205 WF centre and spread 11 ( -0.057359, 1.524062, 0.234488 ) 0.81913192 WF centre and spread 12 ( 0.207447, 1.892500, 0.488594 ) 1.06292460 WF centre and spread 13 ( -0.090800, 0.000000, 1.575406 ) 0.88848488 WF centre and spread 14 ( 0.012349, 0.000000, 7.957177 ) 0.88317336 WF centre and spread 15 ( 0.012349, 1.892503, 3.935322 ) 0.88317159 WF centre and spread 16 ( -0.090800, 1.892500, 0.803094 ) 0.88848495 Sum of centres and spreads ( 0.005703, 15.139999, 57.083998 ) 14.39721976 -------------- next part -------------- Final State WF centre and spread 1 ( 0.000000, 0.000000, 1.913455 ) 1.16247952 WF centre and spread 2 ( 0.000000, 0.000000, 7.509543 ) 1.20049037 WF centre and spread 3 ( 0.000000, 1.892500, 4.382956 ) 1.20048903 WF centre and spread 4 ( 0.000000, 1.892500, 0.465045 ) 1.16247952 WF centre and spread 5 ( 0.000000, 0.000000, 2.004457 ) 1.20048828 WF centre and spread 6 ( 0.000000, 0.000000, 7.600545 ) 1.16248168 WF centre and spread 7 ( 0.000000, 1.892500, 4.291955 ) 1.16248025 WF centre and spread 8 ( 0.000000, 1.892497, 0.374043 ) 1.20048827 WF centre and spread 9 ( 0.000000, 0.000000, 1.522196 ) 0.75151445 WF centre and spread 10 ( 0.000000, 0.000000, 7.991803 ) 0.75151691 WF centre and spread 11 ( 0.000000, 1.892500, 3.900696 ) 0.75151511 WF centre and spread 12 ( 0.000000, 1.892501, 0.856304 ) 0.75151453 WF centre and spread 13 ( 0.000000, 0.000000, 2.312422 ) 0.68819033 WF centre and spread 14 ( 0.000000, 0.000000, 7.201578 ) 0.68819219 WF centre and spread 15 ( 0.000000, 1.892500, 4.690922 ) 0.68819114 WF centre and spread 16 ( 0.000000, 1.892502, 0.066078 ) 0.68819026 Sum of centres and spreads ( 0.000000, 15.139999, 57.083998 ) 15.21070184 From marzari at MIT.EDU Mon Dec 18 03:54:23 2006 From: marzari at MIT.EDU (Nicola Marzari) Date: Sun, 17 Dec 2006 21:54:23 -0500 Subject: [Wannier] Question about final spreads In-Reply-To: References: Message-ID: <458602DF.4050502@mit.edu> Dear Hai-Ping, I believe Michel Posternak has published a paper on Ti02 Wannier functions. It would be interesting to compare your results to his. Our consensus was that the localization functional can display minima that are not meaningful - usually marked by the fact that the MLWFs do not look localized, or symmetric, and especially that they are not real-valued, but are complex-valued. These incorrect minima are somewhat connected to the fact that there are few points in the BZ where a smooth continuous choice of phase factors was not achieved. There are cases when more than one good minimum can exist - the first one that comes to my mind is benzene, where you can have two equivalent choices for the location of the three double bonds on the aromatic ring. It could be that yours is another case - there is more that one meanigful minimum - and, the notion of "meaningful minimum" is rather heuristic. Let us know what you find, nicola lan haiping wrote: > Dear All, > > I came to confusion about final results of wannierise procedure. > I am trying to analyse anatase tio2 wannier function and born charge > with wannier90.x. > I performed 2 calculations with 2 different projection functions sets, > other settings are same. Both reached convergenc (error deltas for total > Omega are about 1E-10). But the total spreads and wannier centers are > quite different. > For my first calculation, i just start with sp2 and pz functions at O > sites, the total spreads finally obtained is 14.397. > While for the second calculation, the projetion functions are s/px/py/pz > functions at O sites, the total spreads finally obtained is then > 15.2170. > > The wannier functions of second calculation could be classed into 4 > groups by spreads , while the conclusion is not hold for the fist > calculation ( the wannier functions are then classed into 8 groups ). > > According to MV paper, the MLWFs reflect structures' symmetry by > spreads. So, Both 2 calculations are not correct. > > Would you please give me some comments ? > And input files are below : > > *num_wann = 16 > num_iter = 2000 > guiding_centres = T > exclude_bands = 1 2 3 4 5 6 7 8 25 26 27 28 29 30 > begin projections > O : sp2 > O : pz > end projections > begin atoms_cart > Ti 0.000000000 -0.000000000 0.000000000 > Ti 0.000000000 1.892500000 2.378500000 > O 0.000000000 0.000000000 1.979863400 > O 0.000000000 -0.000000000 7.534136600 > O 0.000000000 1.892500000 4.358363400 > O 0.000000000 1.892500000 0.398636600 > end atoms_cart* > > *begin unit_cell_cart > Ang > 1.8925 -1.8925 4.757 > 1.8925 1.8925 4.757 > -1.8925 -1.8925 4.757 > end unit_cell_cart > mp_grid : 6 6 6 > begin kpoints > ...... > end kpoints* > > two final spreads and wannier centers are attached. > > *Regards* > > Hai-Ping > > > > -- > Hai-Ping Lan > Department of Electronics , > Peking University , Bejing, 100871 > > > ------------------------------------------------------------------------ > > Final State > WF centre and spread 1 ( -0.057359, 0.368438, 2.144012 ) 0.81913203 > WF centre and spread 2 ( -0.057359, -0.368438, 2.144012 ) 0.81913201 > WF centre and spread 3 ( 0.207447, 0.000000, 1.889906 ) 1.06292459 > WF centre and spread 4 ( -0.197679, 0.225730, 7.480939 ) 0.95045581 > WF centre and spread 5 ( -0.197683, -0.225729, 7.480937 ) 0.95045348 > WF centre and spread 6 ( 0.383935, 0.000000, 7.384053 ) 0.82485652 > WF centre and spread 7 ( -0.197693, 2.118226, 4.411569 ) 0.95044526 > WF centre and spread 8 ( -0.197669, 1.666767, 4.411555 ) 0.95046140 > WF centre and spread 9 ( 0.383935, 1.892503, 4.508447 ) 0.82485530 > WF centre and spread 10 ( -0.057359, 2.260938, 0.234488 ) 0.81913205 > WF centre and spread 11 ( -0.057359, 1.524062, 0.234488 ) 0.81913192 > WF centre and spread 12 ( 0.207447, 1.892500, 0.488594 ) 1.06292460 > WF centre and spread 13 ( -0.090800, 0.000000, 1.575406 ) 0.88848488 > WF centre and spread 14 ( 0.012349, 0.000000, 7.957177 ) 0.88317336 > WF centre and spread 15 ( 0.012349, 1.892503, 3.935322 ) 0.88317159 > WF centre and spread 16 ( -0.090800, 1.892500, 0.803094 ) 0.88848495 > Sum of centres and spreads ( 0.005703, 15.139999, 57.083998 ) 14.39721976 > > > ------------------------------------------------------------------------ > > Final State > WF centre and spread 1 ( 0.000000, 0.000000, 1.913455 ) 1.16247952 > WF centre and spread 2 ( 0.000000, 0.000000, 7.509543 ) 1.20049037 > WF centre and spread 3 ( 0.000000, 1.892500, 4.382956 ) 1.20048903 > WF centre and spread 4 ( 0.000000, 1.892500, 0.465045 ) 1.16247952 > WF centre and spread 5 ( 0.000000, 0.000000, 2.004457 ) 1.20048828 > WF centre and spread 6 ( 0.000000, 0.000000, 7.600545 ) 1.16248168 > WF centre and spread 7 ( 0.000000, 1.892500, 4.291955 ) 1.16248025 > WF centre and spread 8 ( 0.000000, 1.892497, 0.374043 ) 1.20048827 > WF centre and spread 9 ( 0.000000, 0.000000, 1.522196 ) 0.75151445 > WF centre and spread 10 ( 0.000000, 0.000000, 7.991803 ) 0.75151691 > WF centre and spread 11 ( 0.000000, 1.892500, 3.900696 ) 0.75151511 > WF centre and spread 12 ( 0.000000, 1.892501, 0.856304 ) 0.75151453 > WF centre and spread 13 ( 0.000000, 0.000000, 2.312422 ) 0.68819033 > WF centre and spread 14 ( 0.000000, 0.000000, 7.201578 ) 0.68819219 > WF centre and spread 15 ( 0.000000, 1.892500, 4.690922 ) 0.68819114 > WF centre and spread 16 ( 0.000000, 1.892502, 0.066078 ) 0.68819026 > Sum of centres and spreads ( 0.000000, 15.139999, 57.083998 ) 15.21070184 -- --------------------------------------------------------------------- Prof Nicola Marzari Department of Materials Science and Engineering 13-5066 MIT 77 Massachusetts Avenue Cambridge MA 02139-4307 USA tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu From lanhaiping at gmail.com Tue Dec 19 03:54:14 2006 From: lanhaiping at gmail.com (lan haiping) Date: Tue, 19 Dec 2006 10:54:14 +0800 Subject: [Wannier] Question about final spreads In-Reply-To: <458602DF.4050502@mit.edu> References: <458602DF.4050502@mit.edu> Message-ID: Dear Nicola, Thank you. I do want to repeat Prof Postermak's works on tio2. Last night, i also tried to change projection functions for rutile tio2. Indeed, i also found there are 2 more minimum spreads founded with different stating projection functions. For rutile case, when i started with s/px/py/pz on O sites, i obtained total spreads of 14.919. while changing projection functions to sp2/pz on O sites, i obtained total spreads of 14.4672. But wannier function centers can both be classified into 4 groups. Regards, Hai-Ping On 12/18/06, Nicola Marzari wrote: > > > > Dear Hai-Ping, > > > I believe Michel Posternak has published a paper on Ti02 Wannier > functions. It would be interesting to compare your results to his. > > Our consensus was that the localization functional can display > minima that are not meaningful - usually marked by the fact that the > MLWFs do not look localized, or symmetric, and especially that they are > not real-valued, but are complex-valued. These incorrect minima are > somewhat connected to the fact that there are few points in the BZ where > a smooth continuous choice of phase factors was not achieved. > > There are cases when more than one good minimum can exist - the first > one that comes to my mind is benzene, where you can have two equivalent > choices for the location of the three double bonds on the aromatic ring. > > It could be that yours is another case - there is more that one > meanigful minimum - and, the notion of "meaningful minimum" is rather > heuristic. > > Let us know what you find, > > nicola > > > > > lan haiping wrote: > > Dear All, > > > > I came to confusion about final results of wannierise procedure. > > I am trying to analyse anatase tio2 wannier function and born charge > > with wannier90.x. > > I performed 2 calculations with 2 different projection functions sets, > > other settings are same. Both reached convergenc (error deltas for total > > Omega are about 1E-10). But the total spreads and wannier centers are > > quite different. > > For my first calculation, i just start with sp2 and pz functions at O > > sites, the total spreads finally obtained is 14.397. > > While for the second calculation, the projetion functions are s/px/py/pz > > functions at O sites, the total spreads finally obtained is then > > 15.2170. > > > > The wannier functions of second calculation could be classed into 4 > > groups by spreads , while the conclusion is not hold for the fist > > calculation ( the wannier functions are then classed into 8 groups ). > > > > According to MV paper, the MLWFs reflect structures' symmetry by > > spreads. So, Both 2 calculations are not correct. > > > > Would you please give me some comments ? > > And input files are below : > > > > *num_wann = 16 > > num_iter = 2000 > > guiding_centres = T > > exclude_bands = 1 2 3 4 5 6 7 8 25 26 27 28 29 30 > > begin projections > > O : sp2 > > O : pz > > end projections > > begin atoms_cart > > Ti 0.000000000 -0.000000000 0.000000000 > > Ti 0.000000000 1.892500000 2.378500000 > > O 0.000000000 0.000000000 1.979863400 > > O 0.000000000 -0.000000000 7.534136600 > > O 0.000000000 1.892500000 4.358363400 > > O 0.000000000 1.892500000 0.398636600 > > end atoms_cart* > > > > *begin unit_cell_cart > > Ang > > 1.8925 -1.8925 4.757 > > 1.8925 1.8925 4.757 > > -1.8925 -1.8925 4.757 > > end unit_cell_cart > > mp_grid : 6 6 6 > > begin kpoints > > ...... > > end kpoints* > > > > two final spreads and wannier centers are attached. > > > > *Regards* > > > > Hai-Ping > > > > > > > > -- > > Hai-Ping Lan > > Department of Electronics , > > Peking University , Bejing, 100871 > > > > > > ------------------------------------------------------------------------ > > > > > Final State > > WF centre and spread 1 ( -0.057359, 0.368438, 2.144012 ) > 0.81913203 > > WF centre and spread 2 ( -0.057359, -0.368438, 2.144012 ) > 0.81913201 > > WF centre and spread 3 ( 0.207447, 0.000000, 1.889906 ) > 1.06292459 > > WF centre and spread 4 ( -0.197679, 0.225730, 7.480939 ) > 0.95045581 > > WF centre and spread 5 ( -0.197683, -0.225729, 7.480937 ) > 0.95045348 > > WF centre and spread 6 ( 0.383935, 0.000000, 7.384053 ) > 0.82485652 > > WF centre and spread 7 ( -0.197693, 2.118226, 4.411569 ) > 0.95044526 > > WF centre and spread 8 ( -0.197669 , 1.666767, 4.411555 ) > 0.95046140 > > WF centre and spread 9 ( 0.383935, 1.892503, 4.508447 ) > 0.82485530 > > WF centre and spread 10 ( -0.057359, 2.260938, 0.234488 ) > 0.81913205 > > WF centre and spread 11 ( - 0.057359, 1.524062, 0.234488 ) > 0.81913192 > > WF centre and spread 12 ( 0.207447, 1.892500, 0.488594 ) > 1.06292460 > > WF centre and spread 13 ( -0.090800, 0.000000, 1.575406 ) > 0.88848488 > > WF centre and spread 14 ( 0.012349, 0.000000, 7.957177 ) > 0.88317336 > > WF centre and spread 15 ( 0.012349, 1.892503, 3.935322 ) > 0.88317159 > > WF centre and spread 16 ( -0.090800 , 1.892500, 0.803094 ) > 0.88848495 > > Sum of centres and spreads ( 0.005703, 15.139999, 57.083998 ) > 14.39721976 > > > > > > ------------------------------------------------------------------------ > > > > > Final State > > WF centre and spread 1 ( 0.000000, 0.000000, 1.913455 ) > 1.16247952 > > WF centre and spread 2 ( 0.000000, 0.000000, 7.509543 ) > 1.20049037 > > WF centre and spread 3 ( 0.000000, 1.892500, 4.382956 ) > 1.20048903 > > WF centre and spread 4 ( 0.000000, 1.892500, 0.465045 ) > 1.16247952 > > WF centre and spread 5 ( 0.000000, 0.000000, 2.004457 ) > 1.20048828 > > WF centre and spread 6 ( 0.000000, 0.000000, 7.600545 ) > 1.16248168 > > WF centre and spread 7 ( 0.000000, 1.892500, 4.291955 ) > 1.16248025 > > WF centre and spread 8 ( 0.000000 , 1.892497, 0.374043 ) > 1.20048827 > > WF centre and spread 9 ( 0.000000, 0.000000, 1.522196 ) > 0.75151445 > > WF centre and spread 10 ( 0.000000, 0.000000, 7.991803 ) > 0.75151691 > > WF centre and spread 11 ( 0.000000, 1.892500, 3.900696 ) > 0.75151511 > > WF centre and spread 12 ( 0.000000, 1.892501, 0.856304 ) > 0.75151453 > > WF centre and spread 13 ( 0.000000, 0.000000, 2.312422 ) > 0.68819033 > > WF centre and spread 14 ( 0.000000, 0.000000, 7.201578 ) > 0.68819219 > > WF centre and spread 15 ( 0.000000, 1.892500, 4.690922 ) > 0.68819114 > > WF centre and spread 16 ( 0.000000 , 1.892502, 0.066078 ) > 0.68819026 > > Sum of centres and spreads ( 0.000000, 15.139999, 57.083998 ) > 15.21070184 > > > -- > --------------------------------------------------------------------- > Prof Nicola Marzari Department of Materials Science and Engineering > 13-5066 MIT 77 Massachusetts Avenue Cambridge MA 02139-4307 USA > tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu > _______________________________________________ > Wannier mailing list > Wannier at quantum-espresso.org > http://www.democritos.it/mailman/listinfo/wannier > -- Hai-Ping Lan Department of Electronics , Peking University , Bejing, 100871 -------------- next part -------------- An HTML attachment was scrubbed... URL: From marzari at MIT.EDU Tue Dec 19 04:48:43 2006 From: marzari at MIT.EDU (Nicola Marzari) Date: Mon, 18 Dec 2006 22:48:43 -0500 Subject: [Wannier] Question about final spreads In-Reply-To: References: <458602DF.4050502@mit.edu> Message-ID: <4587611B.3040207@mit.edu> Thanks - I also remember that in our work on MnO we needed really very very accurate minimizations to get to the true minimum - it's described a bit in the 2002 PRB with Posternak (we needed 10000-50000 steps, albeit the algorithm now is much better). So I wonder if, by continuing the minimization for many more iterations, you would actually converge to a unique minimum. nicola lan haiping wrote: > Dear Nicola, > > Thank you. > I do want to repeat Prof Postermak's works on tio2. > Last night, i also tried to change projection functions for rutile > tio2. Indeed, i also found there > are 2 more minimum spreads founded with different stating projection > functions. > > For rutile case, when i started with s/px/py/pz on O sites, i obtained > total spreads of 14.919. while changing projection functions to sp2/pz > on O sites, i obtained total spreads of 14.4672. > But wannier function centers can both be classified into 4 groups. > > Regards, > > Hai-Ping -- --------------------------------------------------------------------- Prof Nicola Marzari Department of Materials Science and Engineering 13-5066 MIT 77 Massachusetts Avenue Cambridge MA 02139-4307 USA tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu