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

Download NaCl_ionicbonding.run

#! /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.


$ADFBIN/adf<<eor
Atoms
 Cl  0.0 0.0 0.0
End
XC
  GGA  BECKE PERDEW
End
BASIS
 Type TZ2P
 Core None
End
charge -1
NumericalQuality Good
relativistic scalar zora
eor

rm logfile
mv TAPE21 Cl_min.t21

$ADFBIN/adf<<eor
Atoms
 Na 0.0 0.0 0.0
End
XC
  GGA  BECKE PERDEW
End
BASIS
 Type TZ2P
 Core None
End
charge 1
NumericalQuality Good
relativistic scalar zora
eor

rm logfile
mv TAPE21 Na_plus.t21

$ADFBIN/adf<<eor
TITLE ionic bonding
EPRINT
   SFO eig ovl
  ORBPOP  20  20
  SubEnd
End
XC
  GGA  BECKE PERDEW
End
Atoms
  Na 0.0 0.0 0.0 f=Na
  Cl  0.0 0.0 2.361 f=Cl 
End
NumericalQuality Good
relativistic scalar zora
Fragments
  Na  Na_plus.t21
  Cl  Cl_min.t21
End
RemoveAllFragVirtuals
eor

rm logfile
mv TAPE21 NaCles.t21

$ADFBIN/adf<<eor
TITLE ionic bonding
EPRINT
  SFO eig ovl
  ORBPOP  20  20
  SubEnd
End
XC
  GGA  BECKE PERDEW
End
Atoms
  Na 0.0 0.0 0.0 f=Na
  Cl  0.0 0.0 2.361 f=Cl 
End
NumericalQuality Good
relativistic scalar zora
Fragments
  Na  Na_plus.t21
  Cl  Cl_min.t21
End
eor

rm logfile
mv TAPE21 NaCl.t21