1. The problem statement, all variables and given/known data It's just that I am curious from the vibrational frequency table in the textbook--could someone tell/explain to me why H2 molecule's vib. frequency is about 4400cm-1, whereas H2+ is 2300cm-1? It just seems bizarre to me that such similar molecule should have different vibrational frequency. 2. Relevant equations maybe v = ω/(2πc)? I am not sure, but I think the equation is related to my question above. 3. The attempt at a solution What I am sure of now is that H2's vib. frequency is about x2 that of H2+....so I wonder if this problem arises from H2+ having less electron, thus more delocalization between two H nuclei?