Example: Analytic Frequencies: CN¶

Download CN_SecDeriv.run

#! /bin/sh


# Calculation of normal modes is requested by specifying in the AMS input:
# Properties
#   NormalModes Yes
# End
# ADF will compute the Hessian analytically if possible.
# If the Hessian cannot be computed analytically, numerical differentiation
# will automatically be used.

# A good quality is specified for the numerical Becke integration to be sure of
# reliable results. In general, it seems advisable to use high accuracy for
# heavy nuclei at the moment, whereas default integration accuracy is usually
# sufficient for light atoms. The precision of the fit may be improved with the
# ZlmFit block keyword.


$AMSBIN/ams <<eor
System
  Symmetrize
  atoms
     N  -1.3  0.0   0.0
     C   0.0  0.0   0.0
  end
  charge -1
end

Task SinglePoint

Properties
  NormalModes Yes
End

Engine ADF
  title CN
  beckegrid
    quality good
  end
  basis
    type DZ
    core None
    CreateOutput Yes
  end
  xc
    lda Xonly
  end
EndEngine

eor