#! /bin/sh

# Example excited state calculations of NpF6, which has a doublet ground state.
# Used is spin restricted open shell Kohn-Sham (ROKS, ROSCF).

# First scalar relativistic excitations are calculated using octahedral symmetry (O(h)).

# Note that ADF reports the irreducible representation (irrep) of the transition density,
# which may not be the symmetry species of the excitation in case of open shell molecules.
# In this case the unpaired electron in the octahedral NpF6 is an a2.u orbital.
# The lowest excitation has a T1.g irrep transition density,
# which means that the symmetry species of this excited state is T2.u
# (T2.u = direct product A2.u times T1.g).
# In this calculation both excitations with the same spin as the ground state 
# (S_excited = S_groundstate, SS) and excitations with a spin 1 higher than the ground state
# (S_excited = S_groundstate + 1, SU) are calculated.

AMS_JOBNAME=NpF6.sym "$AMSBIN/ams" << eor
Task SinglePoint
System
    Atoms
        Np 0.0   0.0   0.0
        F  0.0   0.0   1.98
        F  0.0   0.0  -1.98
        F  0.0   1.98  0.0
        F  0.0  -1.98  0.0
        F  1.98  0.0   0.0
        F -1.98  0.0   0.0
    End
End

Engine ADF
    Basis
        Type TZP
        Core None
    End
    Unrestricted Yes
    SpinPolarization 1
    Scf
        ROSCF
        End
    End
    NumericalQuality Good
    TDA
    Excitations
        RoksTddftType
            Calculate SS-SU
        End
        Lowest 6 2
    End
EndEngine
eor

# Next excitations are calculated with perturbative spin-orbit coupling,
# for this open shell molecule, using the keyword SOPERT. Symmetry can not be used.
# In this calculation both excitations with the same spin as the ground state 
# (S_excited = S_groundstate) and excitations with a spin 1 higher than the ground state
# (S_excited = S_groundstate + 1) are calculated.

# With the subkey Excitations%Lowest one can specify the number of wanted excited states.
# If 2 numbers are provided the first number is the wanted excited states with same spin
# and the second number the wanted excited states with higher spin.
# For open shell excitations typically the excited states with higher spin than
# the ground state are higher in energy than those of the excited states with
# the same spin as the ground state.

AMS_JOBNAME=NpF6.soc "$AMSBIN/ams" << eor
Task SinglePoint
System
    Atoms
        Np 0.0   0.0   0.0
        F  0.0   0.0   1.98
        F  0.0   0.0  -1.98
        F  0.0   1.98  0.0
        F  0.0  -1.98  0.0
        F  1.98  0.0   0.0
        F -1.98  0.0   0.0
    End
End

Engine ADF
    Basis
        Type TZP
        Core None
    End
    Unrestricted Yes
    SpinPolarization 1
    Scf
        ROSCF
        End
    End
    Symmetry NOSYM 
    NumericalQuality Good
    TDA
    Excitations
        RoksTddftType
            Calculate SS-SU
        End
        Lowest 6 2
    End
    SOPERT
    End
EndEngine
eor