Example: G_0W_0@PBE calculation: H2O
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"Download GW_H2O.run"

   #! /bin/sh

   # GW calculation for Water. By default. The highest 5 occupied and lowest 5
   # unoccupied states are calculated.

   # We use an all-electron basis set since core-correlation effects are important

   # For H2O, PBE will be a suitable reference since it is only weakly correlated and the 
   # KS HOMO-LUMO gap will be reasonably large.

   # RECOMMENDED: Good numerical quality 

   $AMSBIN/ams << eor
   Symmetry
     SymmetrizeTolerance 0.001
   End

   System
     Atoms
       O    2.220871067   0.026716792   0.000620476
       H    2.597492682  -0.411663274   0.766744858
       H    2.593135384  -0.449496183  -0.744782026
     End
     Symmetrize Yes
   End

   task SinglePoint

   Engine adf
     Basis
       Core None
       Type TZ2P
     end

     NumericalQuality GOOD
     RIHartreeFock fitsetQuality=Normal dependencyThreshold=1e-3
     Dependency bas=1e-4

     XC
       GGA PBE
     end

     GW
        nstates 3
     END
   EndEngine
   eor
