I've found them, just in case someone else will be interested: vibrational and rotational constants of diatomic molecules can be found in Herzberg - Spectra of diatomic molecules
Hi,
I have finished an experiment about vibronic transitions for the N_2 molecule and I'd like to compare my results ( vibrational frequencies and dissociation energies of the electronic states interested in the N_2 second positive and N+_2 first negative band systems ) with the accepted...