Thanks Marcos,
you are right.
Then, it must be the dimer issue which kills the magnetism?
It would make sense to stop after some few iterations
and have a look at the magnetic moments
(and at the structure, e.g. the XV file, as well)

Best regards

Andrei


> Hi Andrei,
>
> Just one comment. If I'm not mistaken, the default spin polarization for
> Siesta, when you don't specify anything, is that one atom is initialized
> with spin up and the other down, in this case - an antiferro
> configuration.
> The final spin of the system could be non zero in this case, I suppose.
>
> Furthermore, I was checking something on Pt and Pd some days ago on the
> siesta mailing list, to see what people had done, and it seems that Pt is
> a
> bordeline case for magnetism, when it comes to wires. Results would differ
> with the use of GGA and LDA - check work by Anna Delin and Erio Tosatti on
> PRL, as well as the associated comment by Simone Alexandre and Jose Soler,
> and the reply to the comment by the authors of the paper.
>
> I just gave it a bird's eye look on the subject, and I recommend a more
> careful look at the siesta mailing list and the corresponding papers.
>
> Best regards,
>
> Marcos
>
> On Fri, Dec 2, 2011 at 8:44 AM, <[email protected]> wrote:
>
>> Dear isivkov,
>>
>> You use
>> SpinPolarized             T    #default
>> but I don't see if you ever made spin up different
>> from spin down (by InitSpin or otherwise).
>> By default, they start equal and remain equal.
>>
>> Moreover:
>> I don't see that you defined
>> AtomicCoordinatesFormat
>> so it must be Bohr by default? -
>> then you probably have Pt2 dimers at 1 Bohr distance,
>> separated by 20 Ang.
>>
>> In addition, i seems weird
>> to construct an empty box of 120 Ang size
>> (in X and Y dimensions), but this has nothing to do
>> with the magnetism issue.
>>
>> Best regards
>>
>> Andrei Postnikov
>>
>>
>> > Hello all.
>> >
>> > I decided to calculate a single atom of platinum, Not exactly single,
>> but
>> > chain of platinum with distance between atoms 10 A. I think it is like
>> a
>> > single atom. My .fdf file is here below. It is very strange, that
>> platinum
>> > is non-magnetic (as you can see from output file below), wile this is
>> the
>> > single atom. Atom of platinum must have magnetic moment.
>> >
>> > My input file
>> > ==================================================================
>> > #
>> >
>> -----------------------------------------------------------------------------
>> > # FDF for Pt bulk
>> > #
>> > # LDA
>> > # Scalar-relativistic pseudopotential with non-linear partial-core
>> > correction
>> > #
>> > #
>> >
>> -----------------------------------------------------------------------------
>> >
>> > #### Cu bulk #######
>> >
>> > SystemName      PtLinChain
>> > SystemLabel     PtLinChain           # Short name for naming files
>> >
>> > # Output options
>> >
>> > WriteCoorStep          true
>> >
>> > WriteMullikenPop       1
>> >
>> > # Species and atoms
>> >
>> > NumberOfSpecies        1
>> > NumberOfAtoms          2
>> >
>> > %block ChemicalSpeciesLabel
>> >   1  78  Pt.LDA
>> > %endblock ChemicalSpeciesLabel
>> >
>> >
>> >
>> > %block PAO.Basis
>> >    Pt.LDA 2 split 0.00  # Species label, number of l-shells
>> >    n=6 0 2 P 1      # n, l, Nzeta, Polarization, NzetaPol
>> >    0.00 0.00        # 0.0 => default [6.982  5.935 \n 1.000  1.000]
>> >    n=5 2 2          # n, l, zeta
>> >    0.00 0.00
>> > %endblock PAO.Basis
>> >
>> >
>> >
>> > LatticeConstant      10  Ang
>> >
>> > %block LatticeVectors
>> >   12.000  0.000  0.000
>> >   0.000  12.000  0.000
>> >   0.000  0.000   2.000
>> > %endblock LatticeVectors
>> >
>> > %block kgrid_Monkhorst_Pack
>> >   1  0  0  0
>> >   0  1  0  0
>> >   0  0  8  0
>> > %endblock kgrid_Monkhorst_Pack
>> >
>> >
>> > XC.functional         LDA           # Exchange-correlation functional
>> > XC.authors            CA            # Exchange-correlation version
>> >
>> > MeshCutoff           150 Ry        # Mesh cutoff. real space mesh
>> >
>> > # SCF options
>> > MaxSCFIterations      200           # Maximum number of SCF iter
>> > DM.MixingWeight       0.02           # New DM amount for next SCF
>> cycle
>> > DM.Tolerance          1.d-4         # Tolerance in maximum difference
>> >                                     # between input and output DM
>> > DM.UseSaveDM          true          # to use continuation files
>> > DM.NumberPulay         5
>> >
>> > Diag.DivideAndConquer  .false.
>> > SolutionMethod         diagon       # OrderN or Diagon
>> > ElectronicTemperature  25 meV       # Temp. for Fermi smearing
>> >
>> > SpinPolarized             T    #default
>> >
>> > # MD options
>> > #MD.TypeOfRun           cg           # Type of dynamics:
>> >
>> > #MD.UseSaveCG         .true.          # for restarting
>> > #MD.UseSaveXV         F               # atomic coords
>> >
>> > #MD.NumCGsteps          0            # Number of CG steps for
>> >                                     #   coordinate optimization
>> > #MD.MaxCGDispl          0.05 Ang      # Maximum atomic displacement
>> >                                     #   in one CG step (Bohr)
>> > #MD.MaxForceTol         0.005 eV/Ang  # Tolerance in the maximum
>> >                                     #   atomic force (Ry/Bohr)
>> >
>> > # Atomic coordinates
>> > AtomicCoordinatesFormat ScaledCartesian
>> >
>> > # %block Zmatrix
>> > #cartesian
>> > #1 0.0000  0.0000  0.0000  1 1 1
>> > #1 0.3535  0.3535  0.5000  1 1 1
>> > #1 0.0000  0.0000  1.0000  1 1 1
>> > #1 0.3535  0.3535  1.5000  1 1 1
>> > #1 0.0000  0.0000  2.0000  1 1 1
>> > #1 0.3535  0.3535  2.5000  1 1 1
>> > #1 0.0000  0.0000  3.0000  0 0 0
>> > #1 0.3535  0.3535  3.5000  0 0 0
>> > #1 0.0000  0.0000  4.0000  0 0 0
>> > #1 0.3535  0.3535  4.5000  0 0 0
>> > # %endblock Zmatrix
>> >
>> > %block AtomicCoordinatesAndAtomicSpecies
>> > 0.0000 0.0000 0.000 1
>> > 0.0000 0.0000 1.000 1
>> > %endblock AtomicCoordinatesAndAtomicSpecies
>> >
>> > #%block GeometryConstraints
>> > #position from 1 to 4
>> > #%endblock GeometryConstraints
>> > =================================================================
>> >
>> >
>> > My output file(parts):
>> > At first SIESTA takes valence configuration from .psf file,
>> > as was in .inp file.
>> > ========================================================
>> > Reading pseudopotential information in formatted form from Pt.LDA.psf
>> >
>> > Pseudopotential generated from an atomic spin-polarized calculation
>> >
>> > Valence configuration for pseudopotential generation:
>> > 6s(1.00,0.00) rc: 2.32
>> > 6p(0.00,0.00) rc: 2.47
>> > 5d(5.00,4.00) rc: 1.23
>> > 5f(0.00,0.00) rc: 2.32
>> > For Pt.LDA, standard SIESTA heuristics set lmxkb to 3
>> >  (one more than the basis l, including polarization orbitals).
>> > Use PS.lmax or PS.KBprojectors blocks to override.
>> >  Warning: Empty PAO shell. l =           1
>> >  Will have a KB projector anyway...
>> > ==========================================================
>> >
>> > than SIESTA writes as though it takes another configuration
>> > with 10 electrons on d-state
>> >
>> > ===========================================================
>> > atm_pop: Valence configuration (for local Pseudopot. screening):
>> >  6s( 0.00)
>> >  6p( 0.00)
>> >  5d(10.00)
>> > Vna: chval, zval:   10.00000  10.00000
>> >
>> > Vna:  Cut-off radius for the neutral-atom potential:   4.341778
>> > comcore: Pseudo-core radius Rcore=  4.234578
>> > ============================================================
>> >
>> > and than that shows absence of magnetic moment after calculation
>> >
>> > ===================================================================
>> > Species: Pt.LDA
>> > Atom  Qatom  Qorb
>> >                6s      6s      5dxy    5dyz    5dz2    5dxz    5dx2-y2
>> > 5dxy
>> >                5dyz    5dz2    5dxz    5dx2-y2 6Ppy    6Ppz    6Ppx
>> >    1  5.000   0.062  -0.006   1.129   1.129   1.130   1.129   1.130
>> > -0.141
>> >              -0.141  -0.141  -0.141  -0.141   0.000   0.000   0.000
>> >    2  5.000   0.062  -0.006   1.129   1.129   1.130   1.129   1.130
>> > -0.141
>> >              -0.141  -0.141  -0.141  -0.141   0.000   0.000   0.000
>> >
>> > mulliken: Qtot =       10.000
>> >
>> > mulliken: Spin DOWN
>> >
>> > Species: Pt.LDA
>> > Atom  Qatom  Qorb
>> >                6s      6s      5dxy    5dyz    5dz2    5dxz    5dx2-y2
>> > 5dxy
>> >                5dyz    5dz2    5dxz    5dx2-y2 6Ppy    6Ppz    6Ppx
>> >    1  5.000   0.062  -0.006   1.129   1.129   1.130   1.129   1.130
>> > -0.141
>> >              -0.141  -0.141  -0.141  -0.141   0.000   0.000   0.000
>> >    2  5.000   0.062  -0.006   1.129   1.129   1.130   1.129   1.130
>> > -0.141
>> >              -0.141  -0.141  -0.141  -0.141   0.000   0.000   0.000
>> >
>> > mulliken: Qtot =       10.000
>> > =========================================================================
>> >
>> >
>> >
>>
>>
>

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