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Dear all,
<br>
I am trying to simulate with CP2K-Quickstep a magnetic surface, in
particular
<br>
a slab of 4 layers of Ni(111).
<br>
I have not manage to converge the system. Here are my
considerations:
<br>
<br>
-) the two dimensional cell is not large (5x5), and I tried
hexagonal and rectangular
<br>
two-dimensiional cells. Since no k-points are considered in CP2K, I
know that
<br>
this cell is rather small, and in order to have converged properties
one should
<br>
use a larger one.
<br>
-) I used the mixing/diagonalization options suggested for metallic
surfaces
<br>
(recent message from Marcella Iannuzzi on the 4th October).
<br>
-) I tried to vary the ALPHA,BETA,NBROYDEN parameters. I also tried
to use
<br>
direct mixing+DIIS scheme. Things did not change much.
<br>
-) I managed to converge the system only with OT scheme, but
although I converge
<br>
the system up to 10<sup class="moz-txt-sup">-7</sup>, the results
does not seem to me converged to the ground state,
<br>
since the magnetic moments of different atoms in the same layer are
not the same,
<br>
while they should be due to symmetric reasons.
<br>
<br>
I made a step back and converged an isolated Ni(111) monolayer, and
in that
<br>
case managed to converge with OT but also with standard
diagonalization+broyden
<br>
mixing, and with the latter scheme I was able to reach always a
converged system
<br>
in terms of equal magnetic moments for all the atoms.
<br>
<br>
I both case (ML and 4 layers slab) I set a multiplicity which is
reasonable
<br>
considering the total moment in the cell that the system should
acquire
<br>
(in case of the ML, I varied also the multiplicity and found the one
giving the
<br>
ground state, while for the 4 layers slab I set it to a reasonable
value,
<br>
could easily be it is not the ground state one).
<br>
<br>
My questions are:
<br>
<br>
1) Are there chances that increasing the two-dimensional cell
dimensions,
<br>
convergence will be reached also for the slab?
<br>
Before trying I would like to have an opinion on that; in other
words, could the dimension
<br>
of the two-dimensional cell be the responsible of the missing
convergence with
<br>
diagonalization+broyden techniques?
<br>
<br>
2) Have anybody ever managed to converged a magnetic surface with
this code?
<br>
<br>
Here is a typical input file I used:
<br>
<br>
&GLOBAL
<br>
ￜ PROJECTￜ ./working
<br>
ￜ RUN_TYPE ENERGY_FORCE
<br>
ￜ PRINT_LEVEL MEDIUM
<br>
&END GLOBAL
<br>
&FORCE_EVAL
<br>
ￜ METHOD Quickstep
<br>
&DFT
<br>
ￜￜￜ BASIS_SET_FILE_NAMEￜ ./BASIS_MOLOPT
<br>
ￜￜￜ POTENTIAL_FILE_NAMEￜ ./GTH_POTENTIALS
<br>
ￜￜￜ RESTART_FILE_NAME ./working-RESTART.wfn
<br>
ￜￜￜ LSD T
<br>
ￜￜￜ MULTIPLICITY 71
<br>
&MGRID
<br>
ￜￜￜￜￜ CUTOFF 500
<br>
ￜￜￜￜￜ NGRIDS 5
<br>
&END MGRID
<br>
&QS
<br>
ￜￜￜￜￜ EXTRAPOLATION PS
<br>
ￜￜￜￜￜ EXTRAPOLATION_ORDER 3
<br>
&END QS
<br>
&SCF
<br>
ￜￜￜￜￜ SCF_GUESS restart
<br>
ￜￜￜￜￜ EPS_SCF 1.0E-7
<br>
ￜￜￜￜￜ MAX_SCF 500
<br>
&OUTER_SCF ON
<br>
ￜￜￜￜￜￜￜ MAX_SCF 20
<br>
ￜￜￜￜￜￜￜ EPS_SCFￜ 1.0E-7
<br>
&END OUTER_SCF
<br>
ￜￜￜￜￜ ADDED_MOS 1000
<br>
&SMEAR ON
<br>
ￜￜￜￜￜￜￜ METHOD FERMI_DIRAC
<br>
ￜￜￜￜￜￜￜ ELECTRONIC_TEMPERATURE [K] 300
<br>
&END SMEAR
<br>
&DIAGONALIZATION ON
<br>
ￜￜￜￜￜￜￜ ALGORITHM STANDARD
<br>
&END DIAGONALIZATION
<br>
&MIXING ON
<br>
ￜￜￜￜￜￜￜ METHOD BROYDEN_MIXING
<br>
ￜￜￜￜￜￜￜ ALPHAￜￜ 0.05
<br>
ￜￜￜￜￜￜￜ BETAￜￜￜ 1.5
<br>
ￜￜￜￜￜￜￜ NBROYDENￜ 8
<br>
&END MIXING
<br>
&END SCF
<br>
&XC
<br>
&VDW_POTENTIAL
<br>
ￜￜￜￜￜￜￜ POTENTIAL_TYPE PAIR_POTENTIAL
<br>
&PAIR_POTENTIAL
<br>
ￜￜￜￜￜￜￜￜￜ REFERENCE_FUNCTIONAL PBE
<br>
ￜￜￜￜￜￜￜￜￜ TYPE DFTD3
<br>
ￜￜￜￜￜￜￜￜￜ PARAMETER_FILE_NAME ./dftd3.dat
<br>
&END PAIR_POTENTIAL
<br>
&END VDW_POTENTIAL
<br>
&XC_FUNCTIONAL
<br>
&PBE
<br>
&END PBE
<br>
&END XC_FUNCTIONAL
<br>
&XC_GRID
<br>
&END XC_GRID
<br>
&END XC
<br>
&END DFT
<br>
&SUBSYS
<br>
&CELL
<br>
ￜￜￜￜￜ PERIODIC XY
<br>
ￜￜￜￜￜ ABC 12.45416482 12.45416482 40
<br>
ￜￜￜￜￜ ANGLES 90 90 120
<br>
&END CELL
<br>
&COORD
<br>
Niￜￜￜￜ 0.000000ￜￜￜￜ 0.000000ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -1.245416ￜￜￜￜ 2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 2.490833ￜￜￜ -4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 1.245416ￜￜￜ -2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 0.000000ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 1.245416ￜￜￜￜ 2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 0.000000ￜￜￜￜ 4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 4.981666ￜￜￜ -4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 3.736249ￜￜￜ -2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 4.981666ￜￜￜￜ 0.000000ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 3.736249ￜￜￜￜ 2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 7.472499ￜￜￜ -4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 6.227082ￜￜￜ -2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 0.000000ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -6.227082ￜￜￜￜ 2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -7.472499ￜￜￜￜ 4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -2.490833ￜￜￜ -4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -3.736249ￜￜￜ -2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 0.000000ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -3.736249ￜￜￜￜ 2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 0.000000ￜￜￜ -4.314249ￜￜￜￜ 7.797460
<br>
Niￜￜￜ -1.245416ￜￜￜ -2.157125ￜￜￜￜ 7.797460
<br>
Niￜￜￜￜ 0.000000ￜￜￜￜ 1.438083ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -1.245416ￜￜￜￜ 3.595208ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 3.736250ￜￜￜ -5.033291ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 2.490833ￜￜￜ -2.876166ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 1.245417ￜￜￜ -0.719042ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 1.438083ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 1.245417ￜￜￜￜ 3.595208ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 6.227082ￜￜￜ -5.033291ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 4.981666ￜￜￜ -2.876166ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 3.736250ￜￜￜ -0.719042ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 4.981666ￜￜￜￜ 1.438083ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 3.736250ￜￜￜￜ 3.595208ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 8.717915ￜￜￜ -5.033291ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 7.472499ￜￜￜ -2.876166ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 6.227082ￜￜￜ -0.719042ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 1.438083ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -6.227082ￜￜￜￜ 3.595208ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -1.245416ￜￜￜ -5.033291ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -2.490833ￜￜￜ -2.876166ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -3.736249ￜￜￜ -0.719042ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 1.438083ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -3.736249ￜￜￜￜ 3.595208ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 1.245417ￜￜￜ -5.033291ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 0.000000ￜￜￜ -2.876166ￜￜￜￜ 9.831216
<br>
Niￜￜￜ -1.245416ￜￜￜ -0.719042ￜￜￜￜ 9.831216
<br>
Niￜￜￜￜ 1.245416ￜￜￜￜ 0.719042ￜￜￜ 11.864973
<br>
Niￜￜￜ -0.000000ￜￜￜￜ 2.876166ￜￜￜ 11.864973
<br>
Niￜￜￜ -1.245417ￜￜￜￜ 5.033291ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 3.736249ￜￜￜ -3.595208ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 2.490833ￜￜￜ -1.438083ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 3.736249ￜￜￜￜ 0.719042ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 2.876166ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 1.245416ￜￜￜￜ 5.033291ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 6.227082ￜￜￜ -3.595208ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 4.981666ￜￜￜ -1.438083ￜￜￜ 11.864973
<br>
Niￜￜￜ -6.227082ￜￜￜￜ 0.719042ￜￜￜ 11.864973
<br>
Niￜￜￜ -7.472499ￜￜￜￜ 2.876166ￜￜￜ 11.864973
<br>
Niￜￜￜ -8.717915ￜￜￜￜ 5.033291ￜￜￜ 11.864973
<br>
Niￜￜￜ -3.736250ￜￜￜ -3.595208ￜￜￜ 11.864973
<br>
Niￜￜￜ -4.981666ￜￜￜ -1.438083ￜￜￜ 11.864973
<br>
Niￜￜￜ -3.736250ￜￜￜￜ 0.719042ￜￜￜ 11.864973
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 2.876166ￜￜￜ 11.864973
<br>
Niￜￜￜ -6.227082ￜￜￜￜ 5.033291ￜￜￜ 11.864973
<br>
Niￜￜￜ -1.245417ￜￜￜ -3.595208ￜￜￜ 11.864973
<br>
Niￜￜￜ -2.490833ￜￜￜ -1.438083ￜￜￜ 11.864973
<br>
Niￜￜￜ -1.245417ￜￜￜￜ 0.719042ￜￜￜ 11.864973
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 2.876166ￜￜￜ 11.864973
<br>
Niￜￜￜ -3.736250ￜￜￜￜ 5.033291ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 1.245416ￜￜￜ -3.595208ￜￜￜ 11.864973
<br>
Niￜￜￜ -0.000000ￜￜￜ -1.438083ￜￜￜ 11.864973
<br>
Niￜￜￜￜ 0.000000ￜￜￜￜ 0.000000ￜￜￜ 13.898730
<br>
Niￜￜￜ -1.245416ￜￜￜￜ 2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 2.490833ￜￜￜ -4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 1.245416ￜￜￜ -2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 0.000000ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 1.245416ￜￜￜￜ 2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 0.000000ￜￜￜￜ 4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 4.981666ￜￜￜ -4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 3.736249ￜￜￜ -2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 4.981666ￜￜￜￜ 0.000000ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 3.736249ￜￜￜￜ 2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 2.490833ￜￜￜￜ 4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 7.472499ￜￜￜ -4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 6.227082ￜￜￜ -2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 0.000000ￜￜￜ 13.898730
<br>
Niￜￜￜ -6.227082ￜￜￜￜ 2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜ -7.472499ￜￜￜￜ 4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜ -2.490833ￜￜￜ -4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜ -3.736249ￜￜￜ -2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜ -2.490833ￜￜￜￜ 0.000000ￜￜￜ 13.898730
<br>
Niￜￜￜ -3.736249ￜￜￜￜ 2.157125ￜￜￜ 13.898730
<br>
Niￜￜￜ -4.981666ￜￜￜￜ 4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜￜ 0.000000ￜￜￜ -4.314249ￜￜￜ 13.898730
<br>
Niￜￜￜ -1.245416ￜￜￜ -2.157125ￜￜￜ 13.898730
<br>
&END COORD
<br>
&KIND Ni
<br>
ￜￜￜￜￜ POTENTIAL GTH-PBE-q18
<br>
ￜￜￜￜￜ BASIS_SET DZVP-MOLOPT-SR-GTH
<br>
&END KIND
<br>
&END SUBSYS
<br>
&END FORCE_EVAL
<br>
<br>
<br>
<br>
<br>
<br>
<br>
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