Example: ESR g-tensor, A-tensor, self consistent spin-orbit coupling: VO
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"Download VO_collinear.run"

   #!/bin/sh


   # The ESR parameters of VO are calculated with the collinear approximation for
   # unrestricted Spin-Orbit coupled calculations. In this example the VO-molecule
   # has three unpaired electrons.

   # You calculate Electron Spin Resonance properties with the keywords ESR and
   # QTENS. ESR is a block-type key and is used to compute the G-tensor or the
   # Nuclear Magnetic Dipole Hyperfine interaction. QTENS is a simple key and
   # invokes the computation of the Nuclear Electric Quadrupole Hyperfine
   # interaction.

   # Proper usage of the key ESR requires that you do one of the following:

   # A Spin-Orbit calculation, spin-restricted, with exactly one unpaired electron,
   # or (b) A Spin-Orbit calculation, spin-unrestricted in the collinear
   # approximation, or (c) No Spin-Orbit terms and spin-unrestricted. In case (a)
   # and (b) you obtain the G-tensor. In case (b) and (c) you get the Magnetic
   # Dipole Hyperfine interaction.

   # Note: in case (a) the program also prints a Magnetic Dipole Hyperfine
   # interaction data, but these have then been computed without the terms from the
   # spin-density at the nucleus. Note: in case (b) and (c) one can have more than
   # one unpaired electron. Note: in case (b) one has to use symmetry NOSYM.

   # Two calculations are performed:

   # Scalar relativistic spin-unrestricted (case c) 
   # Spin-Orbit relativistic spin-unrestricted collinear (case b) 

   # We first calculate the Dipole Hyperfine interaction: 
   # a spin- unrestricted calculation without Spin-Orbit coupling.

   # Note that one has to use ALLPOINTS in the calculation for a linear molecule to
   # get results for the nuclear magnetic dipole hyperfine interaction. For an
   # accurate calculation of the hyperfine interaction the numerical quality is set
   # to VeryGood.

   AMS_JOBNAME=scalar $AMSBIN/ams <<eor
   System
     atoms
        V 0 0 0
        O 0 0 1.589
     End
   End

   Task SinglePoint

   Engine ADF
     AllPoints
     
     ESR
     End
     
     QTens

     ZFS

     basis
       core None
       type TZ2P
     End
     
     numericalquality verygood
     
     relativity
       level scalar
       formalism ZORA
     end
     
     Unrestricted
     SpinPolarization 3
     XC
       GGA Becke Perdew
     End
   EndEngine

   eor

   # Then a spin-orbit coupled spin-unrestricted calculation is performed using the
   # collinear approximation. Note that symmetry NOSYM is used.

   AMS_JOBNAME=so $AMSBIN/ams <<eor
   System
     atoms
        V 0 0 0
        O 0 0 1.589
     End
   End

   Task SinglePoint

   Engine ADF
     ESR
     End
     
     QTens
     
     basis
       core None
       type TZ2P
     End
     
     numericalquality verygood
     
     relativity
       level spin-orbit
       formalism ZORA
       spinorbitmagnetization collinear
     end
     
     SCF
       AccelerationMethod LISTf
     End
     
     symmetry nosym

     Unrestricted
     
     XC
       GGA Becke Perdew
     End
   EndEngine

   eor
