Example: Excitation energies and polarizability: Au2
****************************************************

"Download Au2_Resp.run"

   #! /bin/sh


   # A calculation of response properties of the Au2 dimer, with ZORA relativistic
   # corrections

   # In the response module infinite symmetries cannot be handled (see the User's
   # Guide), so we specify a lower subgroup in the input file, here D(8h).

   # In this sample run the LB94 potential is used. The implementation implies that
   # the XC potential is evaluated from the exact charge density, rather than the
   # cheaper and faster fitted density (as is the case for other XC functionals).
   # This means that the computation times are longer. In a small molecule like Au2
   # this hardly shows, but in larger molecules the differences may be more
   # significant. Note that the LB94 is a model potential, thus the calculated bond
   # energy has not so much meaning. If the BASIS key is specified and the model
   # potential LB94 is used, in the create run of the atoms the BP86 functional is used.

   # Excitation energies are computed, in principle the lowest 10 in each irrep of
   # the symmetry (see the User's Guide for more details).

   $AMSBIN/ams <<eor
   System
     atoms
        Au   0.0 0.0 1.236
        Au   0.0 0.0 -1.236
     end
   end

   Task SinglePoint

   Engine ADF
     title Au2, Response Properties
     excitations
       lowest 10
       tolerance 1e-10
     end
     basis
       PerAtomType Symbol=Au File=ZORA/DZ/Au.4d
     end
     response
       allcomponents
     end
     symmetry D(8h)
     xc
       gga LB94
     end
   EndEngine

   eor
