[CPMD-list] Geometry Optimization of O on Pt slab

[Xudong Tang]

hi, CPMD users,

I'm tring to use CPMD simulating the adsorbed position of Oxygen atom on Pt 
slab. But with local spin density approximation, the force initialization 
process is very slow, which needs like 600+ step to get converged. Does 
anyone here have the experience to accelerate this iteration?

Thanks.

Xudong

Below is the input file for Pt(100) surface:
------------------------------------------------------------------------
&CPMD
    OPTIMIZE GEOMETRY
    LSD
    UNIT HESSIAN
    BFGS
    FREE ENERGY FUNCTIONAL
    LANCZOS DIAGONALISATION
    LANCZOS PARAMETERS
      1  6 15   1.D-18
    TROTTER FACTOR
      0.001
    BOGOLIUBOV CORRECTION OFF
    GRAM-SCHMIDT ORTHOGONALISATION
    CONVERGENCE
      5.D-4   1.D-3
    MAXSTEP
      5000
    BROYDEN MIXING
      0.15 200   0.01  0   10
    ALEXANDER MIXING
      1.1
    ELECTRON TEMPERATURE
      1000.
    COMPRESS WRITE32
    STRUCTURE BONDS

    ANDERSON MIXING
      0.03
&END


&SYSTEM
   MULTIPLICITY
    3

   POINT GROUP
    AUTO
   SYMMETRY
    8
   CELL
    3.94    1    4     0.0  0.0  0.0    (alat=3.94, b/a=1 c/a=8* 1/2)
   CUTOFF
    50.000
   ANGSTROMS
   STATES
    90
   SCALE
   TESR
     3
   KPOINTS MONKHORST-PACK fULL
    4 4 4
&END



&ATOMS
*Pt-q10 KLEINMAN-BYLANDER
   LMAX=F LOC=S
   6
    0         0                 0
    1/2       1/2               0
    1/2       0                 1/8
    0         1/2               1/8
    0         0                 2/8
    1/2       1/2               2/8

*O-q6 KLEINMAN-BYLANDER
  LMAX=P
   2
   0         1/2                25/64
   1/2         0                25/64

  CONSTRAINTS
   FIX ATOMS
    2
    1  2
  END CONSTRAINTS
&END


&DFT
   NEWCODE
   FUNCTIONAL LDA
&END

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