#! /bin/sh

# Application of the non-collinear approach in spin-orbit coupled 
# calculations on Cr3 using a spin-polarized start-up potential
# that has a different magnetization direction in each region.

# In the non-collinear approach by default ADF uses in the first SCF
# cycle an artificial magnetic field in the z-direction that only 
# affects spin (spin-Zeeman term).
# In this example a different artificial magnetic field is included
# that can have a different orientation in different regions.
# This is similar as using a spin-polarized start-up potential, however,
# with the key SpinOrbitMagnetization one can also choose an arbitrary
# magnetization direction.

# Remark: keys MODIFYSTARTPOTENTIAL and RESTART%spinflip can not be used
# in spin-orbit coupled calculations. The key SpinOrbitMagnetization
# should be used instead.

$AMSBIN/ams <<eor
System
  atoms
    Cr      -0.76594   -1.292    0.0    region=r1
    Cr      -0.76594    1.292    0.0    region=r2
    Cr       1.49188    0.000    0.0    region=r3
  End
End

Task SinglePoint

Engine ADF
  relativity
    Level spin-orbit
    SpinOrbitMagnetization NonCollinear
  end
  Basis
    type TZP
    core none
  End
  symmetry nosym
  SpinOrbitMagnetization
    PerRegion
      region r1
      direction  -0.76594   -1.292    0.0
    End
    PerRegion
      region r2
      direction  -0.76594    1.292    0.0
    End
    PerRegion
      region r3
      direction   1.49188    0.000    0.0
    End
  End
  unrestricted
EndEngine
eor