Subject: TDDFT - MO's

From: [email-masked]
Date: Tue, 9 Oct 2001 16:19:12 +0200

Dear CCLers,

TDDFT (at least Gaussian outputs) give information on transition energy,
oscillator strengths, and the
MO's envolved in the respective transition.

  Excitation energies and oscillator strengths:

  Excited State   1:   Singlet-B1     8.0068 eV  154.85 nm  f=0.0142
       3 -> 14        -0.01126
       5 ->  6         0.69120
       5 -> 11         0.01351

with the coefficients defining only the alpha electron. The question now is:

There is a lot of discussion if the basis set (which even in HF theory is only a
model for the real AO's), which
represents the real electron density of the whole state, can be used for
interpretation as MO's. It seems to be
accepted, that these auxiliary functions usually are able to represent the
frontier orbitals reasonably well. But
can we then really interpret these orbitals as the ones from and to which
electrons are excited? Is this model
stable and can it be interpreted photochemically?
I am not aware of any publication dealing with this.

Best regards

Andreas Goeller

P.S.: I will summarize the results.