[Pw_forum] USPP for Bi
Dear Wang, you can find it from the pslibrary. On Fri, May 3, 2013 at 5:54 PM, Q.J.Wang wrote: > Dear Quantum ESPRESSO developers, I need a uspp of Bi now, could you give > one to me if you have it. Thank you very much for your selfless help! > > > -- > Best regards > > Q.J.Wang > > XiangTan University > > > > ___ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Thanks and Regards Bramha Prasad Pandey Indian School of Mines(ISM) Dhanbad, INDIA. -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/c84cf588/attachment.html
[Pw_forum] USPP for Bi
Dear Quantum ESPRESSO developers, I need a uspp of Bi now, could you give one to me if you have it. Thank you very much for your selfless help! -- Best regards Q.J.Wang XiangTan University -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/7aaf8881/attachment.html
[Pw_forum] electron-phonon interaction Spectral function a2F(w) is negative.
Dear all: When i computed the electron-phonon interaction,the a2F(w) was negative but approching to zero,for example: 0.00913 0.00364 3.5E-4 -9.8E-4 -0.00113 -8.4E-4 -5.6E-4 -5.2E-4 -7.5E-4 My question is how much does it effect the electron-phonon coupling constant and Tc. Thanks for your answers. -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/82d8a833/attachment.html
[Pw_forum] Electro-optic tensor contribution
Dear all: In the Electro-optic tensor calculation, it writes in the OUTPUT file: *" Electro-optic tensor: contribution # 1* *.* * Electro-optic tensor: contribution # 2* *"* Which one is ionic contribution? Which one is electronic contribution? Thanks in advance ?? -- Hui Wang School of physics, Fudan University, Shanghai, China -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/9e7f36bf/attachment.html
[Pw_forum] PHonon versions 5.0.2/5.0.3 can give very different frequencies as compared to older versions and the latest SVN builds
Hi everyone, I recently came across some phonon softening in a system calculated with the 5.0.2 version of QE. This came as a surprise because, in addition to having some physical reasons for not believing it, it was in contrast to previous calculations I had done some time back on the same system (and input files) with QE 4.3.2. The deviations with respect to QE version over a 3x3x3 grid of q vectors in this system amounted to a maximal error of 13.5 cm^-1 for a particular q vector. This previously mentioned system was fairly large, so I tried to find simpler systems to run so that I could narrow down where the problem was coming from. I found that many simple systems (like cubic diamond) exhibited essentially zero error regardless of version. However, in guessing that the problem could possibly be related to systems with hexagonal symmetry, I chose to test the hexagonal diamond phase of Ge (4 atoms/cell) and found that over a 3x3x3 grid of q vectors, I got deviations on the order of 95 cm^-1 for some q vectors. I actually do not think the problem is limited to hexagonal symmetry systems however, as I've seen some deviations in other orthorhombic systems (although they have been more minor). Using the hexagonal diamond system, I tested a wide variety of QE releases and SVN versions. The problem occurs for the more recent releases of 5.0.2 and 5.0.3 (i.e., the patch doesn't fix the problem). The latest SVN version is consistent with 5.0.1 and 5.0.0 as well as older versions tested (4.3.2 and 4.2.1). I'm not sure the exact SVN version where the problem first occurred, but rev 9724 is the first commit which gives the "correct" phonon frequencies. Rev 9724 differs from 9723 as follows: login1$ svn -r 9723:9724 diff > Index: PHonon/PH/sgam_ph.f90 > === > --- PHonon/PH/sgam_ph.f90 (revision 9723) > +++ PHonon/PH/sgam_ph.f90 (revision 9724) > @@ -161,7 +161,8 @@ > sym(irot) = sym(irot) .and. (abs(raq(ipol)-aq(ipol)) < 1.0d-5) > enddo > endif > - if (.not.minus_q) then > +! if (.not.minus_q) then > + if (sym(irot).and..not.minus_q) then > raq = - raq > minus_q = eqvect (raq, aq, zero, accep) > endif Anyway, hope these tests are useful. Unless I've made a mistake somewhere, I think it suggests that it's extremely dangerous to do phonon calculations with 5.0.2 or 5.0.3 and you should either stick to 5.0.1 or svn revision 9724 or later. Best, Brad Malone Harvard University -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/c9347638/attachment.html
[Pw_forum] Charge density at any k-point in the Brillouin
Thanks Prof. Paulatto and Prof. Giannozzi for the clarification.
With Regards,
Koushik
JNCASR
Bangalore-560064
>
> Dear PW users,
> I need some clarifications on the input file of pp.x. In the
> namelist, what does the "kpoint" mean?
> To be specific, If I want to visualize the charge density of a
> particular band ("kband") at any arbitrary k-point in the Brillouin
> zone (e.g at Gamma (0, 0, 0) and Z(0, 0, 0.5)) what "kpoint" (integer)
> values should I specify in each case in the namelist?
> Thanks in advance.
Dear Koushik,
the charge density is obtained after a sum over the occupied k-points
and bands, so you cannot print it for a single k-point.
On the other hand, you can plot the contribution from a specific point
"k" and band "n", which is the square modulus of the wavefunction
\psi_{k,n}.
The value of "kpoint" in is the index of the k-point, as listed
in the output of pw.x. If you want to plot a specific point that is not
in the list you will have to do a nscf calculation first.
best regards
--
Dr. Lorenzo Paulatto
IdR @ IMPMC -- CNRS & Universit? Paris 6
phone: +33 (0)1 44275 084 / skype: paulatz
www: http://www-int.impmc.upmc.fr/~paulatto/
mail: 23-24/4?16 Bo?te courrier 115, 4 place Jussieu 75252 Paris C?dex 05
--
Message: 5
Date: Thu, 02 May 2013 15:47:01 +0200
From: Paolo Giannozzi <paolo.gianno...@uniud.it>
Subject: Re: [Pw_forum] Charge density at any k-point in the Brillouin
zone
To: PWSCF Forum
Message-ID: <1367502421.5282.1.camel at fe12lx.fisica.uniud.it>
Content-Type: text/plain; charset="UTF-8"
On Thu, 2013-05-02 at 18:27 +0530, koushik pal wrote:
> To be specific, If I want to visualize the charge density of a
> particular band ("kband") at any arbitrary k-point in the Brillouin
> zone (e.g at Gamma (0, 0, 0) and Z(0, 0, 0.5)) what "kpoint" (integer)
> values should I specify in each case in the namelist?
kpoint is the index of k-points as they appear in the output of pw.x
P.
--
Paolo Giannozzi, Dept. Chemistry,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222
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[Pw_forum] Pression explose
Dear, I am doing MD calculation in QuantumEspresso-5.0.1, and have a question now... ion_dynamics='verlet', ion_temperature='rescale-v', tempw= 300.D0, nraise=20, the pressure "explose" entering subroutine stress ... total stress (Ry/bohr**3) (kbar) P= 2.07818609 -0.00035530 -0.00032388 305711.68-52.27-47.64 -0.00035530 2.07808402 0.00031769-52.27 305696.66 46.73 -0.00032388 0.00031769 2.07750616-47.64 46.73 305611.66 there is someone have the same problem? thanks in advance Sakhraoui Taoufik PhD student LMCN, MONASTIR, TUNISIA -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/ed4d3a53/attachment.html
[Pw_forum] "not orthogonal operation" during vc-relax when optimizing graphene
Dear all, Recently, I just want to putting 'vc-relax' to optimize the graphene structure, but it repots an error: %% from checkallsym : error # 2 not orthogonal operation %% And I set 'cell_dofree = xy' in the vc-relax run. I know, it is no need to apply vc-relax to graphene, and only relax can aquire my result. But if I want to relax bi-layer and mutilayer graphene and my ultimate goal is to get their phonon dispersion curves(so the symmetry should not be broken), how could I do? Is there any convienient method to relax them? Thanks a lot. Yours, Peng Tao -- --- PH.D. candidate Peng Tao Magnetism and Magnetic Materials Division National Laboratory for Material Science Institute of Metal Research, Chinese Academy of Sciences Phone +86-024-83978751 ---
[Pw_forum] "not orthogonal operation" during vc-relax when optimizing graphene
Dear Peng, The cell you might be using is 'hexagonal' and the 'vc-relax' that you are doing has two degrees of freedom in x and y direction which are orthogonal due the flag 'cell_dofree = xy' you set. Since the symmetry is breaking in the second step due to relaxation in x and y direction it is changing the number of k-points. That's why you are getting that error. A simple work-around for this is you use a bit bigger cell with orthorhombic symmetry (in which you have orthogonal 'a' and 'b' vectors). In orthorhombic cell symmetry won't break due to 'cell_dofree = xy'. On Fri, May 3, 2013 at 4:13 AM, Peng Tao wrote: > Dear all, > > Recently, I just want to putting 'vc-relax' to optimize the graphene > structure, > but it repots an error: > > %% > from checkallsym : error # 2 > not orthogonal operation > > %% > > And I set 'cell_dofree = xy' in the vc-relax run. > > I know, it is no need to apply vc-relax to graphene, and only relax can > aquire > my result. But if I want to relax bi-layer and mutilayer graphene and my > ultimate > goal is to get their phonon dispersion curves(so the symmetry should not > be broken), > how could I do? Is there any convienient method to relax them? > > Thanks a lot. > > Yours, > Peng Tao > > -- > --- > PH.D. candidate Peng Tao > Magnetism and Magnetic Materials Division > National Laboratory for Material Science > Institute of Metal Research, Chinese Academy of Sciences > Phone +86-024-83978751 > --- > > > > ___ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Regards, MOHNISH, - Mohnish Pandey, PhD Student, Center for Atomic Scale Materials Design, Department of Physics, Technical University of Denmark - -- next part -- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130503/02743303/attachment.html
