Example: Constrained DFT: H2O+ … H2O

Download WaterDimer.run

#!/bin/sh


# Example of Constrained Density Functional Theory (CDFT) for the charged Water
# dimer, in which the charge is constrained to be on one of the waters. In this
# case there is one constraint, with a total charge of 1.0 on the atoms 1-3.

$AMSBIN/ams <<eor
System
  atoms
     O         0.0000000000        0.0000000000      0.0000000000
     H        -0.9358409558        0.2646136961      0.0000000000
     H        -0.0304663436       -0.9828924420      0.0000000000
     O         0.0000000000       -2.9053396088      0.0000000000
     H        -0.4092227596       -3.3374838250     -0.7701260000
     H        -0.4092227596       -3.3374838250      0.7701260000
  end
  charge 1
end

Task SinglePoint

Engine ADF
  title water dimer h2o+ ... h2o
  
  cdft
    constraints 1.0
    natomsperset 3
    nconstraints 1
    theatoms 1 2 3
  end
  
  basis
    core none
    type TZP
  end
  
  unrestricted
  spinpolarization 1
  
  symmetry NOSYM
  
  xc
    gga PW91
  end
  
  noprint BAS FUNCTIONS
  eprint
    sfo NOEIG NOOVL NOORBPOP
  end
EndEngine

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