The key difference between electronic rotational and vibrational transition is that electronic transitions occur between different electronic states while rotational transitions occur in the same vibrational state and vibrational transitions occur in the same electronic state.
Electronic, rotational and vibrational transitions can be described as properties of molecules. We can investigate molecular structure as a parallel study to the atomic structure using the methods of quantum mechanics and the information obtained from molecular spectra. The most common molecular spectra include electronic, rotational and vibrational transitions.
