Example: External electric field
********************************

"Download EField.run"

   #! /bin/sh

   # Induce a dipole moment in benzene by applying a field orthogonal to the ring

   for EField in 0 0.051422 0.51422 5.1422 ; do # which is 0.001 0.01 0.1 in atomic units

   AMS_JOBNAME=benzene_$EField $AMSBIN/ams << eor

   Task SinglePoint
   System
       Atoms
           C  2.09820318  1.21139817   0.0
           C -0.69940106  1.21139817   0.0
           C  1.39880212  0.0          0.0
           C  1.39880212  2.42279634   0.0
           C  0.0         2.42279634   0.0
           C  0.0         0.0          0.0
           H  3.18949204  1.21139817   0.0
           H  1.94444655  3.36788021   0.0
           H -0.54564443  3.36788021   0.0
           H -1.79068992  1.21139817   0.0
           H -0.54564443 -0.94508387   0.0
           H  1.94444655 -0.94508387   0.0
       End
       ElectrostaticEmbedding
           ElectricField 0.0 0.0 $EField
       End
   End

   Engine MOPAC
   EndEngine

   eor

   done

   # If I apply an electric field of 1 [a.u.] (51.42 Volt/Angstrom = 1 a.u.) on a system with charge 1,
   # I expect the net force to be equal to the 1 [a.u.]

   AMS_JOBNAME=OH_plus $AMSBIN/ams << eor

   Task SinglePoint
   System
       Atoms
           O 0.0 0.0 0.0
           H 1.0 0.0 0.0
       End
       Charge 1
       ElectrostaticEmbedding
           ElectricField 0.0 51.422 0.0
       End
   End

   Properties
       Gradients Yes
   End

   Engine MOPAC
   EndEngine

   eor

