Hyperpol: Hyperpolarizabilities of He and H₂

Sample directory: adf/Hyperpol/

This sample illustrates the computation of (hyper) polarizability tensors for the He atom and the H₂ molecule.

The symmetry is specified, because the Response module in ADF cannot yet handle the infinite symmetries ATOM, C(lin), D(lin).

$ADFBIN/adf <<EOR
Title expt geometrie H2(VII),VWN
noprint sfo,frag,functions

Symmetry C(8v)

Atoms
  H 0 0 -0.37305    
  H 0 0  0.37305   
End

Fragments
  H t21.H7
End

Response
  HyperPol 0.03
  DynaHyp 
  AllComponents
End

EField 0 0 0.001

end input
EOR

The Response data block specifies (AllComponents) that not only the (default) zz-dipole polarizability is to be computed, but the complete tensor. The subkey HyperPol instructs the program to compute hyperpolarizabilities and not only polarizabilities. The DynaHyp subkey implies that the frequency-dependent (hyper)polarizability is calculated. In that case the main laser frequency has to be specified, in hartree units, after the HyperPol subkey.

Only the first hyperpolarizability has been implemented in ADF. Some information on second hyperpolarizabilities can be obtained from the calculation of the first one in a finite field (EFIELD).

In similar fashion the frequency-dependent hyperpolarizability is computed for He, but only the zzz-component because now the AllComponents subkey is omitted.

$ADFBIN/adf <<EOR
Title hyperpolarizability He with the LB94 potential
noprint sfo,frag,functions

Atoms
  He 0 0 0
End

XC
  GGA LB94
END

Fragments
  He t21.He8
End

Response
  HyperPol 0.07
  DynaHyp 
End

integration 5.0

EField 0 0 0.001

Symmetry C(8v)

end input
EOR