Example: TD-DFT+TB: Singlet excited state geometry optimization¶

Download EGO_TD-DFTB.run

#!/bin/sh


# Excited state geometry optimization using TD-DFT+TB, for the molecule m-Cresol.
# The lowest singlet excited state S1 is optimized.
# This method is meant for GGA or LDA functionals. In this example PBE
# 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.

$AMSBIN/ams <<eor
System
  atoms
     C    -1.885     0.511    -0.236
     C    -1.213    -0.724    -0.202
     C     0.201    -0.869    -0.029
     C     1.002     0.345    -0.018
     C     0.289     1.570     0.081
     C    -1.111     1.718     0.028
     C     0.871    -2.198     0.048
     O     0.982     2.797     0.335
     H    -2.954     0.574    -0.397
     H    -1.791    -1.644    -0.345
     H     2.054     0.328    -0.314
     H    -1.578     2.668     0.285
     H     1.958     2.608     0.558
     H     1.664    -2.297    -0.731
     H     0.152    -3.015    -0.093
     H     1.370    -2.341     1.021
  end
end

Task GeometryOptimization

Engine ADF
  excitations
    onlysing
    td-dftb
  end
  basis
    core none
  end
  symmetry NOSYM
  xc
    gga PBE
  end
  excitedGO
    singlet
    state A 1
  end
EndEngine
eor