ricc2 magnetic transition dipole moment

[toda]

Hello,

I'm working on TM 6.1, and have a question for ricc2 method.

How is the magnetic transition dipole moment displayed in output file (ricc2.out)?

Please tell me about the keyword in $excitations, such as diplen, dipvel or qudlen.

In other words, I want to know the part of '?' in the bottom.

$excitations
  irrep=a  multiplicity=  1  nexc=  30  npre=  30  nstart=  30
  spectrum  states=all  operators=diplen,dipvel,angmom,?

Thanks,

Toda

[christof.haettig]

As you probably know from your elementary quantum mechanics lessons, the magnetic dipole
operator is up to a constant factor identical with the angular momentum operator (angmom).
So it's 'angmom' what you need.

The transition dipole moment is not observable and not well defined in coupled-cluster theory.
What you can compute are the oscillator or rotatory strengths or in general the transition
strength for any operator pair. It's described in the manual and the literature referenced therein.

Christof

[Yoshito Nakai]

Thank you very much, Christof.
I have one more question.
What is the unit of transition strength in ricc2.out (diplen, and angmom)?