[Pw_forum] charge density output format from pp.x
On Apr 4, 2011, at 21:25 , jorge.gallardo at cab.cnea.gov.ar wrote: > I need the electronic density rho(x,y,z) for a further calculation. modify one of the many postprocessing codes that manipulate the charge density P. --- Paolo Giannozzi, Dept of Chemistry, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
[Pw_forum] Pw_forum] Shift of Energy
On Mon, 2011-04-04 at 13:56 -0300, Eduardo Ariel Menendez Proupin wrote: > Density functional theory: a practical introduction > David S. Sholl,Janice A. Steckel interesting reference! > 72/8 > 9. > 694/9 > 77. > 694/9-76.276 > .8351 > So, where does the 7 Ry difference arise? 694-76.276*9=7.516 :-) P. -- Paolo Giannozzi, Dept. Chemistry, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
[Pw_forum] Average.x
Dear pwscf users Could any one help me about average.x input parameters? I cant find anything about it in the help files of espresso. Thanks in advance Meysam PAzoki SUT -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/6f82ac1e/attachment.htm
[Pw_forum] charge density output format from pp.x
> you can extract the charge density (with pp.x) in a number of different > formats. For the relation between indices and positions in real space: > http://www.quantum-espresso.org/user_guide/node23.html > thank you for you response. I tried to do something like that, but I cannot understand the content of the file "al.rho.dat". I suppose that the density is in the big block of 6 numerical columns "DATAGRID_3D_UNKNOWN", but, How is ordered that block? , In what order should I read it?. I need the electronic density rho(x,y,z) for a further calculation. thank you again. jorge
[Pw_forum] Van der Waals
I have two questions about the calculations with VdW forces (input_dft = 'vdW-DF'): 1- Is it possible to perform VdW calculations with any kind of functional? Or is it mandatory to use revPBE? 2- I generated a VdW table on two different machines (sp6 of CINECA, matrix of CASPUR). I got different numbers in the files vdW_kernel_table (sign and order of magnitude are different in many cases). Could it depend on the modules I loaded on matrix? Which are the libraries used to generate the table? Adriano -- Universit? degli Studi Tor Vergata via della Ricerca Scientifica 1 00133 Roma, Italia Tel. +39 06 7259 4741 Fax +39 06 2023507
[Pw_forum] Average.x
On Mon, 2011-04-04 at 17:06 +0430, meysam pazoki wrote: > Could any one help me about average.x input parameters? > I cant find anything about it in the help files of espresso. from the user's guide, PostProcessing section: "All codes for which input documentation is not explicitly mentioned have documentation in the header of the fortran sources" P. -- Paolo Giannozzi, Dept. Chemistry, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
[Pw_forum] Average.x
You should read the first few lines of the source file PP/average.f90, the input is explained there. HTH GS Il giorno 04/apr/2011, alle ore 14.36, meysam pazoki ha scritto: > Dear pwscf users > Could any one help me about average.x input parameters? > I cant find anything about it in the help files of espresso. > Thanks in advance > Meysam PAzoki > SUT > > ___ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum ? Gabriele Sclauzero, EPFL SB ITP CSEA PH H2 462, Station 3, CH-1015 Lausanne -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/6b027a45/attachment.htm
[Pw_forum] Pw_forum] Shift of Energy
Hi Pari, I think you should read this book. Density functional theory: a practical introduction David S. Sholl,Janice A. Steckel http://books.google.com/books?id=Q8iNmtswLWYC=frontcover=Janice+Steckel++Sholl=bl=BBHL-SfWoi=HLO4FmyafC7bKh22C0Qf1353Lug=es=KfaZTaajFImatwfQ95iVDA=X=book_result=result=1=0CBcQ6AEwAA#v=onepage=false 72/8 9. 694/9 77. 694/9-76.276 .8351 So, where does the 7 Ry difference arise? Best regards Eduardo Menendez Departamento de Fisica Facultad de Ciencias Universidad de Chile Phone: (56)(2)9787439 URL: http://fisica.ciencias.uchile.cl/~emenendez > > > -- Mensaje reenviado -- > From: pari shok > To: pw_forum at pwscf.org > Date: Mon, 4 Apr 2011 10:32:53 -0400 > Subject: [Pw_forum] Shift of Energy > Dear All, > Thank you very much for your help. > Please let me ask my final question w.r.t DOS shift of energy of SiC > supercell. > The total energy of the 8-atom cell of SiC is: -76.276 Ry, while that of > 72-atom SiC is -694 Ry. Neglecting almost -7 Ry, the total energy is scaling > accordingly. > However, I still see the shift of energy in DOS diagram of two slabs (the > max and min of bandgap shifts, although the gap is almost 2.1 eV for both > 4H-SiC slabs). I was wondering whether this shift of energy is inevitable or > it is as the result of my input file. > I kept k points (w.r.t. crystal), and cut off energy the same for both > structures. Should I scale the cut off energy as well. If positive, is there > any relation between scaling the cell and cut off energy. > As you know, I need to find a reference for my further calculations. > I really really appreciate your help. > Yours > P Shok > > > -- -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/67d0ffbe/attachment.htm
[Pw_forum] shift of energy
Dear All, let me clarify a little point. The potential (hence the eigenvalues) of any calculation in periodic boundary conditions, not just a plane-wave one , is defined up to an additive constant... In a finite system a reeference can be fixed by requiring that the potential goes to zero at infinite distance but in a periodic system this cannot be defined as there is nothing like a point at infinite distance ... In most codes (and in pw.x) this arbitrary constant is fixed by setting the average electrostatic potential to zero. If the supercell is properly constructed, with the properly scaled dimensions, the same cutoff, equivalent k-points etc.. the two calculations should be equivalent and the eigenvalues should be exactly mapped, the average potential should be the same, the total energy should be an exact multiple of the one of the original cell. If this does not happen one is NOT doing the supercell calculation properly. So if when doing a supercell you do not get the scaled result check your system definition. stefano On 04/04/2011 11:46 AM, Giuseppe Mattioli wrote: > Dear all > I suspect that a a little misunderstanding has been going on here... > I try to reformulate the question: in the case of a 8-atoms cell the valence > band maximum (VBM) has been found around 10 eV and the conduction band > minimum (CBM) around 12 eV with a 2 eV band gap. So there is a shift in the > position of VBM and CBM when calculated in a 72-atoms supercell, but the band > gap value is the same. Then, the answer to P Shok could be: plane wave > pseudopotential calculations do not ensure an universal alignment of > eigenvalues. You should use some "internal" reference, like the 1s eigenvalue > of an He atom, in your cell; or trust that the two VBM values are aligned "de > facto". > HTH > > Giuseppe > > On Monday 04 April 2011 09:39:18 Gabriele Sclauzero wrote: >> Yes, >> >> I perfectly agree with Eyvaz! Moreover the experimental bandgap is >> underestimated within LDA or GGA, and for 4H-SiC you would get about >> 2.2-2.3 eV with LDA. >> >> How do you measure the bandgap? Beware that in the fundamental cell the >> bandgap is not a direct one, but it might become such when you use a >> supercell (because of the refolding of the Brillouin zones). >> >> >> HTH >> >> GS >> >> Il giorno 03/apr/2011, alle ore 10.59, Eyvaz Isaev ha scritto: >>> Hi, >>> The bandgap of 8-atoms is around 10-12 eV, but that of 72-atom is around 5-7 eV. >>> This is unbelievable, as SiC is an indirect band gap semiconductor and >>> the bandgap is around (2.5 - 3)eV depending on crystal modification >>> (3C-SiC, 2H-SiC; 4H-SiC; 6H-SiC, etc.). >>> See http://www.matprop.ru/SiC_bandstr >>> >>> So, check carefully your input/output files. >>> >>> Bests, >>> Eyvaz. >>> >>> --- >>> Prof. Eyvaz Isaev, >>> Department of Physics, Chemistry, and Biology (IFM), Linkoping >>> University, Sweden Theoretical Physics Department, Moscow State Institute >>> of Steel& Alloys, Russia, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com >>> >>> >>> From: pari shok >>> To: pw_forum at pwscf.org >>> Sent: Sun, April 3, 2011 1:34:51 AM >>> Subject: [Pw_forum] shift of energy >>> >>> Dear Paolo, >>> DOS of 72-atom SiC shows a shift of energy with respect to 8-atom SiC.The >>> bandgap of 8-atoms is around 10-12 eV, but that of 72-atom is around 5-7 >>> eV. Would you please help me to understand this shift. >>> >>> Thanks again. >>> P Shok >>> UMD >>> >>> On Apr 1, 2011, at 21:36 , pari shok wrote: The DOS of 72-atom SiC (supercell) shows a shift of energy. >>> a shift with respect to what? >>> --- >>> Paolo Giannozzi, Dept of Chemistry, >>> >>> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy >>> Phone +39-0432-558216, fax +39-0432-558222 >>> >>> ___ >>> Pw_forum mailing list >>> Pw_forum at pwscf.org >>> http://www.democritos.it/mailman/listinfo/pw_forum >> ? Gabriele Sclauzero, EPFL SB ITP CSEA >> PH H2 462, Station 3, CH-1015 Lausanne > >
[Pw_forum] Teter''extended norm conserving'' pseudotential
On Mon, Apr 4, 2011 at 9:29 AM, wrote: > Send Pw_forum mailing list submissions to >pw_forum at pwscf.org > > To subscribe or unsubscribe via the World Wide Web, visit >http://www.democritos.it/mailman/listinfo/pw_forum > or, via email, send a message with subject or body 'help' to >pw_forum-request at pwscf.org > > You can reach the person managing the list at >pw_forum-owner at pwscf.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Pw_forum digest..." > > > Today's Topics: > > 1. Van der Waals (Adriano Mosca Conte) > 2. Shift of Energy (pari shok) > 3. Re: Shift of Energy (Duy Le) > 4. Re: 4.3 compile error. (?S) > > > -- > > Message: 1 > Date: Mon, 4 Apr 2011 15:27:08 +0200 (CEST) > From: "Adriano Mosca Conte" > Subject: [Pw_forum] Van der Waals > To: Pw_forum at pwscf.org > Message-ID: <59184.141.108.248.78.1301923628.squirrel at 141.108.248.78> > Content-Type: text/plain;charset=iso-8859-1 > > I have two questions about the calculations with VdW forces > (input_dft = 'vdW-DF'): > 1- Is it possible to perform VdW calculations with any kind of functional? > Or is it mandatory to use revPBE? > 2- I generated a VdW table on two different machines (sp6 of CINECA, > matrix of CASPUR). I got different numbers in the files vdW_kernel_table > (sign > and order of magnitude are different in many cases). Could it depend on the > modules I loaded on matrix? Which are the libraries used to generate > the table? > Adriano > > > -- > Universit? degli Studi Tor Vergata > via della Ricerca Scientifica 1 > 00133 Roma, Italia > Tel. +39 06 7259 4741 > Fax +39 06 2023507 > > > -- > > Message: 2 > Date: Mon, 4 Apr 2011 10:32:53 -0400 > From: pari shok > Subject: [Pw_forum] Shift of Energy > To: pw_forum at pwscf.org > Message-ID:
[Pw_forum] Teter ''extended norm-conserving'' pseudopotential
On Mon, Apr 4, 2011 at 9:29 AM, wrote: > Send Pw_forum mailing list submissions to >pw_forum at pwscf.org > > To subscribe or unsubscribe via the World Wide Web, visit >http://www.democritos.it/mailman/listinfo/pw_forum > or, via email, send a message with subject or body 'help' to >pw_forum-request at pwscf.org > > You can reach the person managing the list at >pw_forum-owner at pwscf.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Pw_forum digest..." > > > Today's Topics: > > 1. Van der Waals (Adriano Mosca Conte) > 2. Shift of Energy (pari shok) > 3. Re: Shift of Energy (Duy Le) > 4. Re: 4.3 compile error. (?S) > > > -- > > Message: 1 > Date: Mon, 4 Apr 2011 15:27:08 +0200 (CEST) > From: "Adriano Mosca Conte" > Subject: [Pw_forum] Van der Waals > To: Pw_forum at pwscf.org > Message-ID: <59184.141.108.248.78.1301923628.squirrel at 141.108.248.78> > Content-Type: text/plain;charset=iso-8859-1 > > I have two questions about the calculations with VdW forces > (input_dft = 'vdW-DF'): > 1- Is it possible to perform VdW calculations with any kind of functional? > Or is it mandatory to use revPBE? > 2- I generated a VdW table on two different machines (sp6 of CINECA, > matrix of CASPUR). I got different numbers in the files vdW_kernel_table > (sign > and order of magnitude are different in many cases). Could it depend on the > modules I loaded on matrix? Which are the libraries used to generate > the table? > Adriano > > > -- > Universit? degli Studi Tor Vergata > via della Ricerca Scientifica 1 > 00133 Roma, Italia > Tel. +39 06 7259 4741 > Fax +39 06 2023507 > > > -- > > Message: 2 > Date: Mon, 4 Apr 2011 10:32:53 -0400 > From: pari shok > Subject: [Pw_forum] Shift of Energy > To: pw_forum at pwscf.org > Message-ID:
[Pw_forum] Shift of Energy
On Mon, Apr 4, 2011 at 10:32 AM, pari shok wrote: > Dear All, > Thank you very much for your help. > Please let me ask my final question w.r.t DOS shift of energy of SiC > supercell. > The total energy of the 8-atom cell of SiC is: -76.276 Ry, while that of > 72-atom SiC is -694 Ry. Neglecting almost -7 Ry, the total energy is scaling > accordingly. If you are doing correctly, the results must be identical. So make sure to check the structures, and the convergence of total energy vs. cutoff energy and k-point sampling. > However, I still see the shift of energy in DOS diagram of two slabs (the > max and min of bandgap shifts, although the gap is almost 2.1 eV for both > 4H-SiC slabs). I was wondering whether this shift of energy is inevitable or > it is as the result of my input file. Slab? I though you are performing bulk calculation. Anyway, the shift of energies' levels is normal. You should set the reference as center of the gap (set it to be zero) then compare the DOS or band structures. By the way, if your bigger slab experiences the reconstruction, the two slabs (8 atoms and 72 atoms) won't be identical => you should not get the same results in this case. But 7Ry seems to be huge. > I kept k points (w.r.t. crystal), and cut off energy the same for both > structures. Should I scale the cut off energy as well. If positive, is there Okie, but you should scale the k-point sampling accordingly because the BZ of 72 atoms cell is smaller. But this won't harm the results if total energy is already converged vs. k-point sampling. > any relation between scaling the cell and cut off energy. No. Cut off energy depends on only pseudo potential. > As you know, I need to find a reference for my further calculations. > I really really appreciate your help. > Yours > P Shok > -- Duy Le PhD Student Department of Physics University of Central Florida. "Men don't need hand to do things" > Dear All, > let me clarify a little point. > The potential (hence the eigenvalues) of any calculation in > periodic boundary conditions, not just a plane-wave one , is defined up > > to an additive constant... In a finite system a reeference can be fixed > by requiring that the potential goes to zero at infinite distance but in > a periodic system this cannot be defined as there is nothing like a > > point at infinite distance ... > In most codes (and in pw.x) this arbitrary constant is fixed by > setting the average electrostatic potential to zero. If the supercell is > properly constructed, with the properly scaled dimensions, the same > > cutoff, equivalent k-points etc.. the two calculations should be > equivalent and the eigenvalues should be exactly mapped, the average > potential should be the same, the total energy should be an exact > multiple of the one of the original cell. > > > If this does not happen one is NOT doing the supercell calculation properly. > > So if when doing a supercell you do not get the scaled result check your > system definition. > > stefano > > > On 04/04/2011 11:46 AM, Giuseppe Mattioli wrote: > >> Dear all >> I suspect that a a little misunderstanding has been going on here... >> I try to reformulate the question: in the case of a 8-atoms cell the >> valence >> band maximum (VBM) has been found around 10 eV and the conduction band > >> minimum (CBM) around 12 eV with a 2 eV band gap. So there is a shift in >> the >> position of VBM and CBM when calculated in a 72-atoms supercell, but the >> band >> gap value is the same. Then, the answer to P Shok could be: plane wave > >> pseudopotential calculations do not ensure an universal alignment of >> eigenvalues. You should use some "internal" reference, like the 1s >> eigenvalue >> of an He atom, in your cell; or trust that the two VBM values are aligned >> "de > >> facto". >> HTH >> >> Giuseppe >> >> On Monday 04 April 2011 09:39:18 Gabriele Sclauzero wrote: >>> Yes, >>> >>> I perfectly agree with Eyvaz! Moreover the experimental bandgap is > >>> underestimated within LDA or GGA, and for 4H-SiC you would get about >>> 2.2-2.3 eV with LDA. >>> >>> How do you measure the bandgap? Beware that in the fundamental cell >>> the > >>> bandgap is not a direct one, but it might become such when you use a >>> supercell (because of the refolding of the Brillouin zones). >>> >>> >>> HTH > >>> >>> GS >>> >>> Il giorno 03/apr/2011, alle ore 10.59, Eyvaz Isaev ha scritto: Hi, > The bandgap of 8-atoms is around 10-12 eV, > > but that of 72-atom is around 5-7 eV. This is unbelievable, as SiC is an indirect band gap semiconductor and the bandgap is around (2.5 - 3)eV depending on crystal modification > (3C-SiC, 2H-SiC; 4H-SiC; 6H-SiC, etc.). See http://www.matprop.ru/SiC_bandstr So, check carefully your input/output files. > Bests, Eyvaz. --- Prof. Eyvaz
[Pw_forum] shift of energy
Dear all I suspect that a a little misunderstanding has been going on here... I try to reformulate the question: in the case of a 8-atoms cell the valence band maximum (VBM) has been found around 10 eV and the conduction band minimum (CBM) around 12 eV with a 2 eV band gap. So there is a shift in the position of VBM and CBM when calculated in a 72-atoms supercell, but the band gap value is the same. Then, the answer to P Shok could be: plane wave pseudopotential calculations do not ensure an universal alignment of eigenvalues. You should use some "internal" reference, like the 1s eigenvalue of an He atom, in your cell; or trust that the two VBM values are aligned "de facto". HTH Giuseppe On Monday 04 April 2011 09:39:18 Gabriele Sclauzero wrote: > Yes, > >I perfectly agree with Eyvaz! Moreover the experimental bandgap is > underestimated within LDA or GGA, and for 4H-SiC you would get about > 2.2-2.3 eV with LDA. > >How do you measure the bandgap? Beware that in the fundamental cell the > bandgap is not a direct one, but it might become such when you use a > supercell (because of the refolding of the Brillouin zones). > > > HTH > > GS > > Il giorno 03/apr/2011, alle ore 10.59, Eyvaz Isaev ha scritto: > > Hi, > > > > >The bandgap of 8-atoms is around 10-12 eV, > > >but that of 72-atom is around 5-7 eV. > > > > This is unbelievable, as SiC is an indirect band gap semiconductor and > > the bandgap is around (2.5 - 3)eV depending on crystal modification > > (3C-SiC, 2H-SiC; 4H-SiC; 6H-SiC, etc.). > > See http://www.matprop.ru/SiC_bandstr > > > > So, check carefully your input/output files. > > > > Bests, > > Eyvaz. > > > > --- > > Prof. Eyvaz Isaev, > > Department of Physics, Chemistry, and Biology (IFM), Linkoping > > University, Sweden Theoretical Physics Department, Moscow State Institute > > of Steel & Alloys, Russia, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com > > > > > > From: pari shok > > To: pw_forum at pwscf.org > > Sent: Sun, April 3, 2011 1:34:51 AM > > Subject: [Pw_forum] shift of energy > > > > Dear Paolo, > > DOS of 72-atom SiC shows a shift of energy with respect to 8-atom SiC.The > > bandgap of 8-atoms is around 10-12 eV, but that of 72-atom is around 5-7 > > eV. Would you please help me to understand this shift. > > > > Thanks again. > > P Shok > > UMD > > > > On Apr 1, 2011, at 21:36 , pari shok wrote: > > > The DOS of 72-atom SiC (supercell) shows a shift of energy. > > > > a shift with respect to what? > > --- > > Paolo Giannozzi, Dept of Chemistry, > > > > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > > Phone +39-0432-558216, fax +39-0432-558222 > > > > ___ > > Pw_forum mailing list > > Pw_forum at pwscf.org > > http://www.democritos.it/mailman/listinfo/pw_forum > > ? Gabriele Sclauzero, EPFL SB ITP CSEA >PH H2 462, Station 3, CH-1015 Lausanne -- - Article premier - Les hommes naissent et demeurent libres et ?gaux en droits. Les distinctions sociales ne peuvent ?tre fond?es que sur l'utilit? commune - Article 2 - Le but de toute association politique est la conservation des droits naturels et imprescriptibles de l'homme. Ces droits sont la libert?, la propri?t?, la s?ret? et la r?sistance ? l'oppression. ? ?Giuseppe Mattioli ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?CNR - ISTITUTO DI STRUTTURA DELLA MATERIA ? ? ?v. Salaria Km 29,300 - C.P. 10 ? ? ? ? ? ? ? ? ? ?I 00015 - Monterotondo Stazione (RM) ? ? ? ? ? ? ?Tel + 39 06 90672836 - Fax +39 06 90672316 ? ? ? ?E-mail:
[Pw_forum] Shift of Energy
ect to 8-atom SiC.The *>>>* bandgap of 8-atoms is around 10-12 eV, but that of 72-atom is around 5-7 *>>>* eV. Would you please help me to understand this shift. *>>>* *>>>* Thanks again. *>>>* P Shok *>>>* UMD *>>>* *>>>* On Apr 1, 2011, at 21:36 , pari shok wrote: *>>>>* The DOS of 72-atom SiC (supercell) shows a shift of energy. *>>>* a shift with respect to what? *>>>* --- *>>>* Paolo Giannozzi, Dept of Chemistry, *>>>* *>>>* Univ. Udine, via delle Scienze 208, 33100 Udine, Italy *>>>* Phone +39-0432-558216, fax +39-0432-558222 *>>>* *>>>* ___ *>>>* Pw_forum mailing list *>>>* Pw_forum at pwscf.org <http://www.democritos.it/mailman/listinfo/pw_forum> *>>>* http://www.democritos.it/mailman/listinfo/pw_forum *>>* ? Gabriele Sclauzero, EPFL SB ITP CSEA *>>* PH H2 462, Station 3, CH-1015 Lausanne *>* *>* * -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/6c0c645c/attachment.htm
[Pw_forum] shift of energy
Yes, I perfectly agree with Eyvaz! Moreover the experimental bandgap is underestimated within LDA or GGA, and for 4H-SiC you would get about 2.2-2.3 eV with LDA. How do you measure the bandgap? Beware that in the fundamental cell the bandgap is not a direct one, but it might become such when you use a supercell (because of the refolding of the Brillouin zones). HTH GS Il giorno 03/apr/2011, alle ore 10.59, Eyvaz Isaev ha scritto: > Hi, > > >The bandgap of 8-atoms is around 10-12 eV, > >but that of 72-atom is around 5-7 eV. > > This is unbelievable, as SiC is an indirect band gap semiconductor and > the bandgap is around (2.5 - 3)eV depending on crystal modification > (3C-SiC, 2H-SiC; 4H-SiC; 6H-SiC, etc.). > See http://www.matprop.ru/SiC_bandstr > > So, check carefully your input/output files. > > Bests, > Eyvaz. > > --- > Prof. Eyvaz Isaev, > Department of Physics, Chemistry, and Biology (IFM), Linkoping University, > Sweden > Theoretical Physics Department, Moscow State Institute of Steel & Alloys, > Russia, > isaev at ifm.liu.se, eyvaz_isaev at yahoo.com > > > From: pari shok > To: pw_forum at pwscf.org > Sent: Sun, April 3, 2011 1:34:51 AM > Subject: [Pw_forum] shift of energy > > Dear Paolo, > DOS of 72-atom SiC shows a shift of energy with respect to 8-atom SiC.The > bandgap of 8-atoms is around 10-12 eV, but that of 72-atom is around 5-7 eV. > Would you please help me to understand this shift. > > Thanks again. > P Shok > UMD > On Apr 1, 2011, at 21:36 , pari shok wrote: > > > The DOS of 72-atom SiC (supercell) shows a shift of energy. > > a shift with respect to what? > --- > Paolo Giannozzi, Dept of Chemistry, > > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > Phone +39-0432-558216, fax +39-0432-558222 > > ___ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum ? Gabriele Sclauzero, EPFL SB ITP CSEA PH H2 462, Station 3, CH-1015 Lausanne -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/3b12b706/attachment.htm
[Pw_forum] How to read two wave-functions in one program?
On Apr 4, 2011, at 8:43 , Stefano Baroni wrote: > shouldn't it rather be exp(+i k*r)? (for the few who would care ...) yes, sure P. --- Paolo Giannozzi, Dept of Chemistry, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
[Pw_forum] How to read two wave-functions in one program?
On Apr 3, 2011, at 6:33 PM, Paolo Giannozzi wrote: > > On Apr 1, 2011, at 7:23 , xuhui luo wrote: >> >> Can you (or anyone) tell me the best way to save wavefunction >> psi(ik, iband, ispin) on a grid of real space > > > just use the real-space FFT grid: wavefunctions are Fourier > transformed all the time from real to reciprocal space. > Remember than wavefunctions in FFT format should be > multiplied by the Bloch factor exp(-i k*r). shouldn't it rather be exp(+i k*r)? (for the few who would care ...) SB --- Stefano Baroni - SISSA & DEMOCRITOS National Simulation Center - Trieste http://stefano.baroni.me [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype) La morale est une logique de l'action comme la logique est une morale de la pens?e - Jean Piaget Please, if possible, don't send me MS Word or PowerPoint attachments Why? See: http://www.gnu.org/philosophy/no-word-attachments.html -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110404/f275132c/attachment-0001.htm
