[Pw_forum] Wrong effective charges in AFM insulator using "zue"
xirainbow
nkxirainbow at gmail.com
Sun Jan 23 12:54:23 CET 2011
Dear professor Andrea Dal Corso:
Thank you very much for your help.
I added "occupations = 'fixed'", "noncolin = .TRUE." and "starting
magnetizations"
However it can not converge in scf circle. I will resolve it by myself.
I have another little question.
The three translational modes are about 70cm^-1 in paramagnetic bulk
material. How can I reduce them below 10cm^-1?(The "conv_thr" in pw.x is
10^-8, and tr2_ph in ph.x is 10^-12.
)
On Wed, Jan 19, 2011 at 6:28 PM, Andrea Dal Corso <dalcorso at sissa.it> wrote:
>
> On Wed, 2011-01-19 at 17:37 +0800, xirainbow wrote:
> > Dear professor Andrea Dal Corso:
> > Thank you for you quickly reply.
> > I follow your suggestion in scf calculation and add noncolin= .TRUE.“
> > with occupations = 'fixed'
> > The calculated absolute magnetization = 0.01 Bohr mag/cell in
> > scf output.
> > However in LSDA+smearing calculation, absolute magnetization =
> > 5.68 Bohr mag/cell.
> > The following is my scf.in. Is there anything wrong?
> > Thank you very much:)
> >
> >
> > &CONTROL
> > calculation = 'scf'
> > title = 'G-10-scf'
> > verbosity = 'high'
> > restart_mode = 'from_scratch'
> > wf_collect = .FALSE.
> > tstress = .TRUE.
> > tprnfor = .TRUE.
> > prefix = 'G-10-scf'
> > etot_conv_thr = 1.0e-4
> > forc_conv_thr = 1.0e-3
> > disk_io = 'low'
> > pseudo_dir = '~/espresso-4.2.1/pseudo'
> > /
> >
> >
> > &SYSTEM
> > ibrav = 2
> > celldm = 14.20419765 !bohr
> > nat = 10
> > ntyp = 4
> > ecutwfc = 70
> > ecutrho = 560
> > nbnd = 100
> > nosym = .FALSE.
> > occupations = 'fixed'
> > noncolin = .TRUE.
>
> Please add the starting magnetizations...
>
> Andrea
>
>
> > /
> >
> >
> > &ELECTRONS
> > electron_maxstep = 100
> > conv_thr = 1.0e-7
> > mixing_mode = 'plain'
> > mixing_beta = 0.7
> > mixing_ndim = 8
> > diagonalization = 'david'
> > diago_david_ndim = 4
> > /
> >
> >
> > ATOMIC_SPECIES
> > Mn1 55 Mn.pbe-sp-van.UPF
> > Mn2 55 Mn.pbe-sp-van.UPF
> > Ca 40 Ca.pbe-nsp-van.UPF
> > O 16 O.pbe-rrkjus.UPF
> >
> >
> > ATOMIC_POSITIONS {crystal}
> > Mn1 0.00 0.00 0.00
> > Mn2 0.50 0.50 0.50
> > Ca 0.25 0.25 0.25
> > Ca 0.75 0.75 0.75
> > O 0.75 0.25 0.75
> > O 0.25 0.75 0.25
> > O 0.75 0.75 0.25
> > O 0.25 0.25 0.75
> > O 0.25 0.75 0.75
> > O 0.75 0.25 0.25
> >
> >
> >
> >
> > K_POINTS {automatic}
> > 6 6 6 0 0 0
> >
> >
> >
> >
> >
> > On Wed, Jan 19, 2011 at 4:41 PM, Andrea Dal Corso <dalcorso at sissa.it>
> > wrote:
> >
> >
> > On Wed, 2011-01-19 at 16:27 +0800, xirainbow wrote:
> > > In 4.2.1 manual, it is said that:If .zue=true.is an
> > alternative
> > > algorithm, different from the default one (if trans .and.
> > epsil ) The
> > > results should be the same within numerical noise.
> > >
> > >
> > > However, I get wrong "effective charges" in zue=true in AFM
> > insulator
> > > CaMnO3 with 4.2.1
> > > These two Mn atoms are the same except antiparallel spin.
> > > In "epsil+trans", effective charges of Mn1=7.79, Mn2=7.78;
> > > In "zue" , effective charges of Mn1=3.1,
> > Mn2=51.2;
> > >
> > >
> > > I will describe my calculation procedure using 4.2.1 in
> > short.
> > > 1: I do scf calculation in scf.in
> > > restart_mode = 'from_scratch'
> > > occupations = 'smearing'
> > > smearing = 'gauss'
> > > degauss = 0.002
> > > starting_magnetization(1) = 1
> > > starting_magnetization(2) = -1
> > > starting_magnetization(3) = 0
> > > starting_magnetization(4) = 0
> > >
> > >
> > > 2: I do a scf calculation in scf.in
> > > restart_mode = 'restart'
> > > occupations = 'fixed'
> > > nspin = 2
> > > tot_magnetization = 0
> > >
> > >
> > > 3: I do ph calculation with
> > > zue = .TRUE. !the same with epsil and trans = TRUE
> > > (In this condition, effective charges of Mn1=3.1,
> > Mn2=51.2;)
> > > or with:
> > > epsil = .TRUE. , trans = .TRUE.
> > > (In this condition , effective charges of Mn1=7.79,
> > Mn2=7.78;)
> > >
> > >
> > > (The reason is why I restart scf is below:
> > > "starting_magnetization" must be used with "smearing".
> > However,
> > > "smearing" will give a metal result. Effective charges can
> > not be
> > > calculated for metal. But, CaMnO3 is really a insulator AFM.
> > > "occupations=fixed" can get a insulator result. However it
> > must used
> > > with "tot_magnetization". If I use "tot_magnetization=0", I
> > will get a
> > > PM no AFM state.
> > > In the end, I use "smearing"+"starting_magnetization" to get
> > a AFM
> > > metal. Then I use "fixed"+"tot_magnetization" to get a AFM
> > insulator.
> > > Is there any other good method to get a AFM insulator?)
> >
> > >
> > >
> > >
> > > The following my script for "zue= .TRUE "
> > > And I have attached output file of "zue= .TRUE " in
> > accessary.
> > > Thanks:)
> >
> >
> > The phonon with LSDA + constraint is not programmed. So it
> > will not
> > work. If the AFM insulator is the ground state then you should
> > obtain it
> > with noncolin=.true. without constraint. In this case ph.x at
> > gamma
> > should work and you should get the correct effective charges.
> > If not
> > please provide the complete input.
> >
> > HTH,
> >
> > Andrea
> >
> >
> >
> >
> > >
> > > #*********************************************
> > > # scf-antimag-smearing
> > > cat>scf.in<<EOF
> > > for vc-relax
> > > &CONTROL
> > > calculation = 'scf'
> > > title = 'G-10-scf'
> > > verbosity = 'high'
> > > restart_mode = 'from_scratch'
> > > wf_collect = .FALSE.
> > > tstress = .TRUE.
> > > tprnfor = .TRUE.
> > > prefix = 'G-10-scf'
> > > etot_conv_thr = 1.0e-4
> > > forc_conv_thr = 1.0e-3
> > > disk_io = 'low'
> > > pseudo_dir = './'
> > > /
> > >
> > >
> > > &SYSTEM
> > > ibrav = 2
> > > celldm = 14.20419765
> > > nat = 10
> > > ntyp = 4
> > > nbnd = 50
> > > ecutwfc = 70
> > > ecutrho = 560
> > > nosym = .FALSE.
> > > !nosym_evc = .TRUE.
> > > !noinv = .TRUE.
> > > occupations = 'smearing'
> > > smearing = 'gauss'
> > > degauss = 0.002
> > > starting_magnetization(1) = 1
> > > starting_magnetization(2) = -1
> > > starting_magnetization(3) = 0
> > > starting_magnetization(4) = 0
> > > !occupations = 'fixed'
> > > nspin = 2
> > > !tot_magnetization = 0
> > > /
> > >
> > >
> > > &ELECTRONS
> > > electron_maxstep = 100
> > > conv_thr = 1.0e-7
> > > mixing_mode = 'plain'
> > > mixing_beta = 0.7
> > > mixing_ndim = 8
> > > diagonalization = 'david'
> > > diago_david_ndim = 4
> > > /
> > >
> > >
> > > ATOMIC_SPECIES
> > > Mn1 55 Mn.pbe-sp-van.UPF
> > > Mn2 55 Mn.pbe-sp-van.UPF
> > > Ca 40 Ca.pbe-nsp-van.UPF
> > > O 16 O.pbe-rrkjus.UPF
> > >
> > >
> > > ATOMIC_POSITIONS {crystal}
> > > Mn1 0.00 0.00 0.00
> > > Mn2 0.50 0.50 0.50
> > > Ca 0.25 0.25 0.25
> > > Ca 0.75 0.75 0.75
> > > O 0.75 0.25 0.75
> > > O 0.25 0.75 0.25
> > > O 0.75 0.75 0.25
> > > O 0.25 0.25 0.75
> > > O 0.25 0.75 0.75
> > > O 0.75 0.25 0.25
> > >
> > >
> > >
> > > K_POINTS {automatic}
> > > 6 6 6 0 0 0
> > > EOF
> > > ./dopw <scf.in >G-scf-10-smearing.out
> > >
> > >
> > > # scf-antimag-insulator
> > > cat>scf.in<<EOF
> > > for vc-relax
> > > &CONTROL
> > > calculation = 'scf'
> > > title = 'G-10-scf'
> > > verbosity = 'high'
> > > restart_mode = 'restart'
> > > wf_collect = .FALSE.
> > > tstress = .TRUE.
> > > tprnfor = .TRUE.
> > > prefix = 'G-10-scf'
> > > etot_conv_thr = 1.0e-4
> > > forc_conv_thr = 1.0e-3
> > > disk_io = 'low'
> > > pseudo_dir = './'
> > > /
> > >
> > >
> > > &SYSTEM
> > > ibrav = 2
> > > celldm = ${lattic_parameter} !bohr
> > > nat = 10
> > > ntyp = 4
> > > nbnd = 50
> > > ecutwfc = 70
> > > ecutrho = 560
> > > nosym = .FALSE.
> > > !nosym_evc = .TRUE.
> > > !noinv = .TRUE.
> > > !occupations = 'smearing'
> > > !smearing = 'gauss'
> > > !degauss = 0.002
> > > !starting_magnetization(1) = 1
> > > !starting_magnetization(2) = -1
> > > !starting_magnetization(3) = 0
> > > !starting_magnetization(4) = 0
> > > occupations = 'fixed'
> > > nspin = 2
> > > tot_magnetization = 0
> > > /
> > >
> > >
> > > &ELECTRONS
> > > electron_maxstep = 100
> > > conv_thr = 1.0e-7
> > > mixing_mode = 'plain'
> > > mixing_beta = 0.7
> > > mixing_ndim = 8
> > > diagonalization = 'david'
> > > diago_david_ndim = 4
> > > /
> > >
> > >
> > > ATOMIC_SPECIES
> > > Mn1 55 Mn.pbe-sp-van.UPF
> > > Mn2 55 Mn.pbe-sp-van.UPF
> > > Ca 40 Ca.pbe-nsp-van.UPF
> > > O 16 O.pbe-rrkjus.UPF
> > >
> > >
> > > ATOMIC_POSITIONS {crystal}
> > > Mn1 0.00 0.00 0.00
> > > Mn2 0.50 0.50 0.50
> > > Ca 0.25 0.25 0.25
> > > Ca 0.75 0.75 0.75
> > > O 0.75 0.25 0.75
> > > O 0.25 0.75 0.25
> > > O 0.75 0.75 0.25
> > > O 0.25 0.25 0.75
> > > O 0.25 0.75 0.75
> > > O 0.75 0.25 0.25
> > >
> > >
> > >
> > > K_POINTS {automatic}
> > > 6 6 6 0 0 0
> > > EOF
> > > ./dopw <scf.in >G-scf-10-insulator.out
> > >
> > >
> > > #for phonon-antimag
> > > cat>ph.in <<EOF
> > > for phonon
> > > &INPUTPH
> > > amass(1) = 55
> > > amass(2) = 55
> > > amass(3) = 40
> > > amass(4) = 16
> > > outdir = "./"
> > > prefix = 'G-10-scf' !must be the same with scf
> > > ldisp = .FALSE.
> > > niter_ph = 100
> > > tr2_ph = 1.0e-12
> > > alpha_mix(1)= 0.7
> > > nmix_ph = 4
> > > iverbosity = 1
> > > fildyn = 'matdyn'
> > > !epsil = .TRUE. !Do not set epsil to .true. for
> > metallic system
> > > or q/=0
> > > !trans = .TRUE. !if trans .and. epsil effective
> > charges are
> > > calculated
> > > zue = .TRUE. !the same with epsil and trans = TRUE
> > > /
> > > 0.0 0.0 0.0
> > > EOF
> > >
> > >
> > > ./doph <ph.in >G-ph-10.out
> > > done
> > > #*********************************************
> > >
> > > --
> > > ____________________________________
> > > Hui Wang
> > > School of physics, Fudan University, Shanghai, China
> >
> > > _______________________________________________
> > > Pw_forum mailing list
> > > Pw_forum at pwscf.org
> > > http://www.democritos.it/mailman/listinfo/pw_forum
> > --
> > Andrea Dal Corso Tel. 0039-040-3787428
> > SISSA, Via Bonomea 265 Fax. 0039-040-3787249
> > I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it
> >
> >
> > _______________________________________________
> > Pw_forum mailing list
> > Pw_forum at pwscf.org
> > http://www.democritos.it/mailman/listinfo/pw_forum
> >
> >
> >
> > --
> > ____________________________________
> > Hui Wang
> > School of physics, Fudan University, Shanghai, China
> >
> > _______________________________________________
> > Pw_forum mailing list
> > Pw_forum at pwscf.org
> > http://www.democritos.it/mailman/listinfo/pw_forum
> --
> Andrea Dal Corso Tel. 0039-040-3787428
> SISSA, Via Bonomea 265 Fax. 0039-040-3787249
> I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>
--
____________________________________
Hui Wang
School of physics, Fudan University, Shanghai, China
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