Example: Convenient way to specify a basis set¶

#! /bin/sh

# This example shows some of the flexibility of the Basis key. The
# defaults are set to a DZ basis set with a Large frozen core. As the example
# shows, it is possible to override the defaults per atom type or to directly
# specify basis set files for particular atom types.

$AMSBIN/ams <<eor

Task SinglePoint

System
   Atoms [Bohr]
      C       0.0   0.0   0.0 region=C
      O       0.0   2.13  0.0 region=O.large_basis
      H       4.0   0.0   0.0 region=H.large_basis
      H       4.0   1.43  0.0 region=H.custom
   End
End

Engine Band
   Title CO + H2: fine tuning the basis defaults

   NumericalQuality Basic

   Basis
      ! Cheap defaults
      Type DZ
      Core Large
      PerRegion Region=C              Core=None    ! This C has no frozen core
      PerRegion Region=O.large_basis  Type=TZ2P    ! This O with a larger basis
      PerRegion Region=H.large_basis  Type=V       ! This one also with a larger basis
      PerRegion Region=H.custom       File=DZ/H
   End
EndEngine
eor