# Database for molecular dipole transition moments?

I'm looking for the dipole transition matrix elements for electronic transitions between the ground and excited states of the carbon dioxide cation, $\text{CO}_2^+$, that is, objects like $$\langle\text{CO}_2^+ \,\tilde{\text{A}}\,\Pi_\text{u}|\mathbf{r}|\text{CO}_2^+ \,\tilde{\text{X}}\,\Pi_\text{g}\rangle.$$ I feel this is a standard enough quantity that it ought to be easy to find in some appropriate database of chemical data. However, I've searched for quite some time and I can't even find something similar.

Where should I be looking?

• For a triatomic molecule, I guess that would be difficult to come by in a database. Molecular Spectra and Molecular Structure III - Electronic Spectra and Electronic Structure of Polyatomic Molecules by G. Herzberg is a good place to start. – Antonio de Oliveira-Filho Sep 26 '18 at 5:48