A couple of references on magnetic platinum & palladium using SIESTA are:
1.Magnetic anisotropies of late transition metal atomic clusters
L. Fernández-Seivane, J. Ferrer
Phys. Rev. Lett. 99, 183401 (2007); arXiv:cond-mat/0610879v2
Erratum: Phys. Rev. Lett. 101, 069903(E) (2008)
2. Predictions for the formation of atomic chains in
MechanicallyControllable Break Junction experiments
Lucas Fernandez-Seivane, Victor M. Garcia-Suarez, Jaime Ferrer
Phys. Rev. B 75, 075415 (2007); arXiv:cond-mat/0611624v1
The problem is with the file periodic_table.f, where the atomic d population for
platinum is set to 10. You have to modify this entry (as well as the entry for
the s-population).
Jaime Ferrer
On 02/12/11 14:22, [email protected] wrote:
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
=========================================================================
