Example: TD-DFT+TB: Open shell excited state geometry optimization
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"Download EGO_TD-DFTB_unrestricted.run"

   #!/bin/sh

   # Excited state geometry optimization using TD-DFT+TB,
   # for the radical cation of Pyrazine (open shell doublet).
   # The lowest unrestricted excited state is optimized.
   # This method is meant for GGA or LDA functionals. In this example LDA functional PW92
   # is used during the SCF. In the the calculation of the excitation energies the
   # TD-DFTB+TB method is used in which the required integrals are approximated in
   # the same way as in a TD-DFTB calculation. Symmetry NOSYM is required.
   # For excited state gradients all electron basis sets are required.

   # Note that for symmetric systems, one could perturb the coordinates
   # to break the symmetry of the system. This can be done, for example,
   # by including PerturbCoordinates 0.05 in the System block.
   # In this example this is not done, which in practice means that the
   # molecule remains symmetric.

   $AMSBIN/ams <<eor
   system
     Atoms
       H 0.000000 2.068464 1.258236
       H 0.000000 -2.068464 1.258236
       H 0.000000 2.068464 -1.258236
       H 0.000000 -2.068464 -1.258236
       C 0.000000 1.135920 0.697884
       C 0.000000 -1.135920 0.697884
       C 0.000000 1.135920 -0.697884
       C 0.000000 -1.135920 -0.697884
       N 0.000000 0.000000 1.417402
       N 0.000000 0.000000 -1.417402
     End
     charge 1
   End

   Task GeometryOptimization

   GeometryOptimization
   END

   Engine adf
     Basis
        Type DZP
        Core none
     End
     XC
       LDA PW92
     End
     SYMMETRY NOSYM
     numericalquality good
     unrestricted Yes
     SpinPolarization 1.0
     EXCITATIONS
       TD-DFTB
       lowest 10
     END
     EXCITEDGO
       STATE A 1
     END
   EndEngine
   eor
