Minima hopping issue

[Ho Chang Song]

Hello CP2K community,

I’m using CP2K together with a minima-hopping (MH) workflow to search for low-energy adsorption geometries of CO on metal clusters.

Even when I start with a CO, many MH-relaxed minima end up with C and O dissociated and adsorbed separately. This is problematic for screening workflows where I want intact CO adsorption geometries.

If anyone has a recommended CP2K/MH input showing a safe/standard way to constrain bonds or to treat small molecules as rigid during MH, I’d be very grateful.
Below is my example input file for these types of calculations.

Thank you in advance,

Hochang

&GLOBAL
   PROJECT_NAME Ag147_minhop
   PROGRAM_NAME SWARM
   RUN_TYPE NONE
&END GLOBAL

&SWARM
   BEHAVIOR GLOBAL_OPT
   NUMBER_OF_WORKERS 21
   MAX_ITER 50000
   &GLOBAL_OPT
     #E_TARGET -0.028421532
     #E_TARGET -0.397492331
     #E_TARGET -0.173928427
     METHOD MINIMA_HOPPING
     &HISTORY
       ENERGY_PRECISION 1.0e-5
       FINGERPRINT_PRECISION 1.0e-2
     &END HISTORY
   &END GLOBAL_OPT
&END SWARM

&MOTION
  &PRINT  ! IO is expensive, turning everything off
    &RESTART OFF
    &END RESTART
    &RESTART_HISTORY OFF
    &END RESTART_HISTORY
    &TRAJECTORY
     !ADD_LAST NUMERIC
      &EACH
        GEO_OPT -1
        MD -1
      &END EACH
    &END TRAJECTORY
  &END PRINT

  &MD
    ENSEMBLE NVE
    STEPS 1000
    TIMESTEP 0.5

    &VELOCITY_SOFTENING
      STEPS 20
      ALPHA 1.0
      DELTA 0.01
    &END VELOCITY_SOFTENING

    &PRINT
      &ENERGY OFF
      &END ENERGY
      &CENTER_OF_MASS OFF
      &END CENTER_OF_MASS
      &COEFFICIENTS OFF
      &END COEFFICIENTS
      &PROGRAM_RUN_INFO OFF
      &END PROGRAM_RUN_INFO
      &ROTATIONAL_INFO OFF
      &END ROTATIONAL_INFO
      &SHELL_ENERGY OFF
      &END SHELL_ENERGY
      &TEMP_KIND OFF
      &END TEMP_KIND
      &TEMP_SHELL_KIND OFF
      &END TEMP_SHELL_KIND
      FORCE_LAST .TRUE.
    &END PRINT
  &END MD

  &GEO_OPT
    OPTIMIZER CG
    MAX_ITER 300
    &CG
      MAX_STEEP_STEPS 3
      &LINE_SEARCH
        &GOLD
          INITIAL_STEP 1.0e-2
        &END GOLD
      &END LINE_SEARCH
    &END CG
    &BFGS
     TRUST_RADIUS [angstrom] 0.1
     USE_RAT_FUN_OPT  ! otherwise LJ particle sth. get too close.
     &RESTART OFF
     &END RESTART
    &END BFGS
    &PRINT
      &PROGRAM_RUN_INFO OFF
      &END PROGRAM_RUN_INFO
    &END PRINT
  &END GEO_OPT

&END MOTION

&FORCE_EVAL
 &PRINT
    &DISTRIBUTION OFF
    &END DISTRIBUTION
    &DISTRIBUTION1D OFF
    &END DISTRIBUTION1D
    &DISTRIBUTION2D OFF
    &END DISTRIBUTION2D
    &FORCES OFF
    &END FORCES
    &GRID_INFORMATION OFF
    &END GRID_INFORMATION
    &PROGRAM_RUN_INFO OFF
    &END PROGRAM_RUN_INFO
    &STRESS_TENSOR OFF
    &END STRESS_TENSOR
    &TOTAL_NUMBERS OFF
    &END TOTAL_NUMBERS
  &END PRINT

 METHOD FIST
  &MM
    &FORCEFIELD
     IGNORE_MISSING_CRITICAL_PARAMS  T
     &SPLINE
       EPS_SPLINE 1.0E-5
       EMAX_SPLINE 10000
     &END SPLINE
     &BOND
       ATOMS C O
       KIND HARMONIC
       R0 [angstrom] 1.13      ! equilibrium distance in angstrom
       K [angstrom^-2kcalmol] 2670      ! force constant (units: energy/(length^2))
     &END BOND
      &NONBONDED
        &EAM
          ATOMS Ag Ag
          PARM_FILE_NAME /global/u1/h/hochang/CP2K/Ag.pot
        &END EAM
        &LENNARD-JONES
        ATOMS Ag C
        EPSILON [kcalmol] 0.15   ! placeholder: replace with literature or mixed value
        SIGMA 2.95
          RCUT    [angstrom] 11.4
        &END LENNARD-JONES
        &LENNARD-JONES
        ATOMS Ag O
        EPSILON [kcalmol] 0.12   ! placeholder: replace with literature or mixed value
        SIGMA 2.8
          RCUT    [angstrom] 11.4
        &END LENNARD-JONES
       &LENNARD-JONES
         atoms C C
         EPSILON [kcalmol]  0.08
          SIGMA   [angstrom] 3.05
          RCUT    [angstrom] 11.4
       &END LENNARD-JONES
        &LENNARD-JONES
          atoms O O
          EPSILON [kcalmol]  0.08
          SIGMA   [angstrom] 3.02
          RCUT    [angstrom] 11.4
        &END LENNARD-JONES
      &END NONBONDED
      &CHARGE
        ATOM Ag
        CHARGE 0.0
      &END CHARGE
      &CHARGE
        ATOM C
        CHARGE 0.0
      &END CHARGE
      &CHARGE
        ATOM O
        CHARGE 0.0
      &END CHARGE
    &END FORCEFIELD
    &NEIGHBOR_LISTS
      GEO_CHECK OFF
    &END NEIGHBOR_LISTS
    &POISSON
    PERIODIC NONE
    POISSON_SOLVER ANALYTIC
      &EWALD
        EWALD_TYPE none
      &END EWALD
    &END POISSON
    &PRINT
      &DERIVATIVES OFF
      &END DERIVATIVES
      &DIPOLE OFF
      &END DIPOLE
      &EWALD_INFO OFF
      &END EWALD_INFO
      &FF_INFO OFF
      &END FF_INFO
      &FF_PARAMETER_FILE OFF
      &END FF_PARAMETER_FILE
      &ITER_INFO OFF
      &END ITER_INFO
      &NEIGHBOR_LISTS OFF
      &END NEIGHBOR_LISTS
      &PROGRAM_BANNER OFF
      &END PROGRAM_BANNER
      &PROGRAM_RUN_INFO OFF
      &END PROGRAM_RUN_INFO
      &SUBCELL OFF
      &END SUBCELL
    &END PRINT
  &END MM
   &SUBSYS
     &CELL
       A     35.00E+00    0.000E+00    0.000E+00
       B     0.000E+00    35.00E+00    0.000E+00
       C     0.000E+00    0.000E+00    35.00E+00
       PERIODIC  NONE
     &END CELL
     &COORD
     @include 'coord.inc'
     &END COORD

    &TOPOLOGY
      CONNECTIVITY OFF
    &END TOPOLOGY

     &KIND Ag
      ELEMENT Ag
      MASS 107.8682
#       BASIS_SET DZVP-MOLOPT-SR-GTH
#       POTENTIAL GTH-PBE-q11
     &END KIND
     &KIND C
      ELEMENT C
      MASS 12.011
#       BASIS_SET DZVP-MOLOPT-SR-GTH
#       POTENTIAL GTH-PBE-q4
     &END KIND
     &KIND O
      ELEMENT O
      MASS 15.999
#       BASIS_SET DZVP-MOLOPT-SR-GTH
#       POTENTIAL GTH-PBE-q6
     &END KIND
   &END SUBSYS
 &END FORCE_EVAL