[QE-users] error in scf calculation using wyckoff positions
Paolo Giannozzi
paolo.giannozzi at uniud.it
Thu Jun 20 10:40:18 CEST 2024
You have three types of atoms so no more than three values of
"starting_magnetization"
Paolo
On 19/06/2024 06:59, Pooja Vyas wrote:
>
> Non si ricevono spesso messaggi di posta elettronica da
> poojavyas at mkbhavuni.edu.in. Informazioni sul perché è importante
> <https://aka.ms/LearnAboutSenderIdentification>
>
>
>
> I tried to compute energy of antiferromagnetic (AFM) V3Al using the
> below script:
>
>
> &CONTROL
> calculation = 'scf'
> prefix = 'v3al'
> outdir = './'
> pseudo_dir = './'
> tprnfor = .true.
> tstress = .true.
> etot_conv_thr = 4.0000000000d-05
> forc_conv_thr = 1.0000000000d-04
> verbosity = 'high'
> /
>
> &SYSTEM
> ibrav = 0
> ! celldm(1) = 11.512210722
> ! space_group = 225
> nat = 16
> ntyp = 3
> ecutwfc = 60
> ecutrho = 400
> occupations = 'smearing'
> smearing = 'cold'
> degauss = 0.005
> nspin = 2
> starting_magnetization(1)=1
> starting_magnetization(2)=-1
> starting_magnetization(3)=1
> starting_magnetization(4)=-1
> starting_magnetization(5)=1
> starting_magnetization(6)=-1
> starting_magnetization(7)=1
> starting_magnetization(8)=-1
> /
>
> &ELECTRONS
> conv_thr = 8.0000000000d-10
> mixing_beta = 4.0000000000d-01
> /
>
> ATOMIC_SPECIES
> Al 26.9815 Al.pbe-nl-rrkjus_psl.1.0.0.UPF
> V1 50.9415 V.pbe-spnl-rrkjus_psl.1.0.0.UPF
> V2 50.9415 V.pbe-spnl-rrkjus_psl.1.0.0.UPF
>
> ATOMIC_POSITIONS {crystal}
> V2 0.2500000000 0.2500000000 0.7500000000
> V2 0.2500000000 0.2500000000 0.2500000000
> V2 0.7500000000 0.7500000000 0.7500000000
> V2 0.7500000000 0.7500000000 0.2500000000
> V2 0.7500000000 0.2500000000 0.7500000000
> V2 0.2500000000 0.7500000000 0.2500000000
> V2 0.2500000000 0.7500000000 0.7500000000
> V2 0.7500000000 0.2500000000 0.2500000000
> Al 0.0000000000 0.0000000000 0.0000000000
> Al 0.0000000000 0.5000000000 0.5000000000
> Al 0.5000000000 0.0000000000 0.5000000000
> Al 0.5000000000 0.5000000000 0.0000000000
> V1 0.5000000000 0.5000000000 0.5000000000
> V1 0.5000000000 0.0000000000 0.0000000000
> V1 0.0000000000 0.5000000000 0.0000000000
> V1 0.0000000000 0.0000000000 0.5000000000
>
> K_POINTS automatic
> 10 10 10 0 0 0
>
> CELL_PARAMETERS angstrom
> 6.092 0.000 0.000
> 0.000 6.092 0.000
> 0.000 0.000 6.092
>
> -------------------------------------------------------------------------
>
> But as the iterations proceed, I see that the values of total and
> absolute magnetisation both approaches zero value.
> total magnetization = 0.03 Bohr mag/cell
> absolute magnetization = 0.14 Bohr mag/cell (This is at
> 27th iteration and calculation is still going as energy is not yet
> converged. So, at final iteration, probably both will become zero)
>
> Shouldn't atleast the absolute magnetisation be nonzero value? I guess
> for AFM, only total magnetisation at the end should be zero.
> I'm saying this because when I had performed AFM calculation for
> chromium, total magnetisation was 0.0 but absolute was 2.28 bohr mag/cell.
> are things going correct? Attached below is the cif file.
>
>
>
> On Tue, Jun 18, 2024 at 4:14 PM Paolo Giannozzi
> <paolo.giannozzi at uniud.it <mailto:paolo.giannozzi at uniud.it>> wrote:
>
> On 6/18/24 08:59, Pooja Vyas wrote:
>
> > space_group = 225
>
> > ATOMIC_POSITIONS {crystal_sg}
> > Al 4a
> > V1 4b
> > V2 8c
> > V3 0.25 0.25 0.75
>
> > Error in routine check_atoms (1):
> > atoms # 3 and # 6 overlap!
>
> they do: atom V3 overlaps with one of the two positions for atoms V2.
> See https://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list
> <https://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list> for
> group 225.
>
> 4a = 4 atoms in the conventional cell (cubic), 1 atom in the primitive
> cell (fcc). Same for 4b and 8c. So you have nat=3 (number of Wyckoff
> positions, not of atoms) and 4 atoms, 1 Al and 3 V, if you set
> ATOMIC_POSITIONS {crystal_sg}
> Al 4a
> V1 4b
> V2 8c
> Note that ntyp=3: there are two different types of V atoms, not three.
> Disclaimer: just guessing
>
> Paolo
>
> > stopping ...
> >
> >
> >
> >
> ----------------------------------------------------------------------------
> >
> > What is causing the issue and what should be changed in the input
> file?
> > Any kind of help is appreciated.
> >
> >
> > *Pooja,
> > *
> > *Research Scholar,*
> > *Department of Physics,*
> > *MKBU,*
> > *Bhavnagar,*
> > *Gujarat.*
> > *
> > *
> >
> > _______________________________________________
> > The Quantum ESPRESSO community stands by the Ukrainian
> > people and expresses its concerns about the devastating
> > effects that the Russian military offensive has on their
> > country and on the free and peaceful scientific, cultural,
> > and economic cooperation amongst peoples
> > _______________________________________________
> > Quantum ESPRESSO is supported by MaX (www.max-centre.eu
> <http://www.max-centre.eu>)
> > users mailing list users at lists.quantum-espresso.org
> <mailto:users at lists.quantum-espresso.org>
> > https://lists.quantum-espresso.org/mailman/listinfo/users
> <https://lists.quantum-espresso.org/mailman/listinfo/users>
>
> --
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216
> X SCUOLA ESTIVA DI ENERGIE RINNOVABILI
> https://scuola-rinnovabili.uniud.it/
> <https://scuola-rinnovabili.uniud.it/>
>
--
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216
X SCUOLA ENERGIE RINNOVABILI 16-21/9/2024 - PRE-ISCRIZIONE
https://agenda.infn.it/event/39573/
More information about the users
mailing list