Example: Geometry optimization for an excited state
***************************************************

"Download GO_LR-TDDFTB_benzene.run"

   #!/bin/sh

   # This test optimizes the geometry of the lowest singlet excitation
   # of benzene. This was an example from Niehaus' original paper on
   # TD-DFTB gradients. See
   #      D. Heringer et al. J. Comput. Chem. 28:2589-2601, 2007
   # for his results and the C-C and C-H bond distances this test
   # should produce.

   $AMSBIN/ams << eor

   Task GeometryOptimization
   GeometryOptimization
      Convergence Gradients=0.0001
   End

   System
       Atoms
         H    0.000000       2.484212      0.000000
         H    0.000000      -2.484212      0.000000
         H    2.151390       1.242106      0.000000
         H   -2.151390      -1.242106      0.000000
         H   -2.151390       1.242106      0.000000
         H    2.151390      -1.242106      0.000000
         C    0.000000       1.396792      0.000000
         C    0.000000      -1.396792      0.000000
         C    1.209657       0.698396      0.000000
         C   -1.209657      -0.698396      0.000000
         C   -1.209657       0.698396      0.000000
         C    1.209657      -0.698396      0.000000
       End
   End


   Engine DFTB
      Model SCC-DFTB
      ResourcesDir DFTB.org/mio-1-1
      Properties
          Excitations
              TDDFTB
                  Calc singlet
                  Lowest 1
                  Diagonalization exact
              End
              TDDFTBGradients
                  Excitation 1
              End
          End
      End
   EndEngine

   eor
