[QE-users] users Digest, Vol 160, Issue 7
Ashis Kundu
ashiskundu174 at gmail.com
Tue Nov 10 20:02:34 CET 2020
On Sun, Nov 8, 2020 at 4:30 PM <users-request at lists.quantum-espresso.org>
wrote:
> Send users mailing list submissions to
> users at lists.quantum-espresso.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
> https://lists.quantum-espresso.org/mailman/listinfo/users
> or, via email, send a message with subject or body 'help' to
> users-request at lists.quantum-espresso.org
>
> You can reach the person managing the list at
> users-owner at lists.quantum-espresso.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of users digest..."
>
>
> Today's Topics:
>
> 1. Re: Mismatch between k-points from scf.out and q-point from
> system.dyn0 (Paolo Giannozzi)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sat, 7 Nov 2020 19:14:02 +0100
> From: Paolo Giannozzi <p.giannozzi at gmail.com>
> To: Quantum ESPRESSO users Forum <users at lists.quantum-espresso.org>
> Subject: Re: [QE-users] Mismatch between k-points from scf.out and
> q-point from system.dyn0
> Message-ID:
> <
> CAPMgbCvHhL3-ZOuySWvLEeF_322XOTVMMRZQ1+9Wfw77CGE_JQ at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> On Fri, Nov 6, 2020 at 11:14 PM Ashis Kundu <ashiskundu174 at gmail.com>
> wrote:
>
> Why is there a mismatch between k-points from SCF and q-point from
> > system.dyn0 (phonon calculation)?
> > [...] Ideally they should be the same
> >
>
> they are the same, but the algorithms for generation and selection of the
> irreducible sector are different for the two grids so the ordering and sign
> may differ. Each of the points in the first set is either equal to or
> equivalent to a point of the second set.
I understand it, but I have never encountered this mismatch (though not
really) before where the system has a different ibrav number than 7.
>
>
Please let me know if I am doing something wrong.
> >
>
> you aren't doing anything wrong. Or maybe you are: the scf input you sent
> cannot produce the k-point grid you listed
>
Sorry I have given the wrong k-mesh. Actually, I generated the listed
k-points using 3x3x3.
Best regards,
Ashis
>
> >
> > The k-points generated from SCF
> >
> > number of k points= 8 Methfessel-Paxton smearing, width (Ry)=
> > 0.0200
> > cart. coord. in units 2pi/alat
> > k( 1) = ( 0.0000000 0.0000000 0.0000000), wk =
> 0.0740741
> > k( 2) = ( -0.3333333 0.0000000 0.0977788), wk =
> 0.2962963
> > k( 3) = ( -0.3333333 0.3333333 0.1955577), wk =
> 0.5925926
> > k( 4) = ( 0.3333333 0.3333333 -0.0000000), wk =
> 0.2962963
> > k( 5) = ( 0.0000000 0.0000000 0.1955577), wk =
> 0.1481481
> > k( 6) = ( 0.6666667 0.0000000 -0.0000000), wk =
> 0.1481481
> > k( 7) = ( 0.0000000 -0.3333333 -0.0977788), wk =
> 0.2962963
> > k( 8) = ( 0.0000000 0.6666667 0.0000000), wk =
> 0.1481481
> >
> > q-point from phonon calculations (a mesh of 3x3x3 is used)
> >
> > 0.00000000 0.00000000 0.00000000
> > -0.33333333 0.00000000 0.09777884
> > 0.00000000 0.33333333 0.09777884
> > -0.33333333 0.33333333 0.19555767
> > 0.33333333 0.33333333 -0.00000000
> > 0.00000000 0.00000000 0.19555767
> > 0.66666667 0.00000000 -0.00000000
> > 0.00000000 -0.66666667 -0.00000000
> >
> > Below are the SCF and phonon input file
> >
> > scf.in
> > -----
> > &control
> > calculation = 'scf'
> > prefix = 'TaP'
> > pseudo_dir = '../pp'
> > outdir = './'
> > wf_collect = .true.
> > tprnfor = .true.
> > tstress = .true.
> > /
> > &system
> > ibrav = 7
> > celldm(1) = 6.173529611
> > celldm(3) = 3.409054
> > nat = 4
> > ntyp = 2
> > ecutwfc = 100
> > occupations = 'smearing'
> > smearing = 'mp'
> > degauss = 0.02
> > /
> > &electrons
> > diagonalization = 'david'
> > mixing_beta = 0.7
> > conv_thr = 1.0d-10
> > /
> > ATOMIC_SPECIES
> > Ta 180.948 Ta.pw-mt_fhi.UPF
> > P 30.974 P.pw-mt_fhi.UPF
> > ATOMIC_POSITIONS {alat}
> > Ta 0.0000000 0.0000000 -0.0044625
> > Ta 0.0000000 0.5000000 0.8478074
> > P 0.0000000 0.0000000 1.4178478
> > P 0.5000000 0.0000000 0.5655748
> > K_POINTS {automatic}
> > 15 15 15 0 0 0
> >
> > ph.in
> > ----
> > phonon
> > &inputph
> > prefix = 'TaP'
> > fildyn = 'TaP.dyn'
> > fildvscf = 'dvscf'
> > ldisp = .true.
> > epsil = .false.
> > nq1 = 3
> > nq2 = 3
> > nq3 = 3
> > tr2_ph = 1.0d-14
> > /
> >
> >
> > Best regards,
> > Ashis
> > _______________________________________________
> > Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> > users mailing list users at lists.quantum-espresso.org
> > https://lists.quantum-espresso.org/mailman/listinfo/users
>
>
>
> --
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <
> http://lists.quantum-espresso.org/pipermail/users/attachments/20201107/597621bb/attachment-0001.html
> >
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> users mailing list
> users at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
>
> ------------------------------
>
> End of users Digest, Vol 160, Issue 7
> *************************************
>
--
_____________________________________
Institute for Advanced Study
Shenzhen University
Shenzhen,Guangdong,China
Ph.: 13143400965
E-mail: ashiskundu174 at gmail.com
k.ashis at szu.edu.cn
______________________________________
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20201111/2ab6142d/attachment.html>
More information about the users
mailing list