Example: Analysis of NaCl using ionic fragments: Na+ and Cl-¶

#! /bin/sh


# This example illustrates advanced usage of the bond energy decomposition
# scheme used in ADF.

# This example shows the energy decomposition analysis of NaCl with
# ionic fragments: Na+ and Cl-
# See also the example with neutral fragments: Na and Cl, both open shell atoms
#
# If the key REMOVEALLFRAGORBITALS is used one can approximately
# see what the electrostatic effect is on the fragment orbitals if one places
# the two ions together.
#
# Another way to see what the electrostatic effect is on the fragment orbitals is
# to use the key 'PRINT FMATSFO' in the full molecule calculation, where one can
# look at the expectation value of the Fock matrix of a fragment orbital in the
# presence of the other fragment.


AMS_JOBNAME=Cl_min $AMSBIN/ams <<eor
System
  atoms
     Cl  0.0 0.0 0.0
  end
  charge -1
end

Task SinglePoint

Engine ADF
  basis
    core None
    type TZ2P
    CreateOutput Yes
  end
  numericalquality Good
  relativity
    level scalar
    formalism ZORA
  end
  xc
    gga BECKE PERDEW
  end
EndEngine
eor

AMS_JOBNAME=Na_plus $AMSBIN/ams <<eor
System
  atoms
     Na 0.0 0.0 0.0
  end
  charge 1
end

Task SinglePoint

Engine ADF
  basis
    core None
    type TZ2P
    CreateOutput Yes
  end
  numericalquality Good
  relativity
    level scalar
    formalism ZORA
  end
  xc
    gga BECKE PERDEW
  end
EndEngine
eor

AMS_JOBNAME=NaCl_es $AMSBIN/ams <<eor
System
  atoms
     Na  0.0 0.0 0.0   adf.f=Na
     Cl  0.0 0.0 2.361 adf.f=Cl
  end
end

Task SinglePoint

Engine ADF
  eprint
    orbpop 20  20
    end
    sfo eig ovl
  end
  fragments
     Na  Na_plus.results/adf.rkf
     Cl  Cl_min.results/adf.rkf
  end
  numericalquality Good
  relativity
    level scalar
    formalism ZORA
  end
  removeallfragvirtuals
  title ionic bonding
  xc
    gga BECKE PERDEW
  end
EndEngine
eor


AMS_JOBNAME=NaCl $AMSBIN/ams <<eor
System
  atoms
     Na 0.0 0.0 0.0 adf.f=Na
     Cl  0.0 0.0 2.361 adf.f=Cl
  end
end

Task SinglePoint

Engine ADF
  eprint
    orbpop 20  20
    end
    sfo eig ovl
  end
  fragments
     Na  Na_plus.results/adf.rkf
     Cl  Cl_min.results/adf.rkf
  end
  numericalquality Good
  relativity
    level scalar
    formalism ZORA
  end
  title ionic bonding
  xc
    gga BECKE PERDEW
  end
EndEngine
eor