- #1
Malamala
- 299
- 27
Hello! If we have a transition between 2 ro-vibrational levels of the same electronic state of a diatomic molecule the selection rules require for the changes in the rotational quantum number J that ##\Delta J = \pm 1##. Why can't we have ##\Delta J = 0##? The photon carries one unit of angular momentum, so if we start with a state with angular momentum J, shouldn't we be able to obtain J-1, J and J+1 by combining it with the 1 unit of angular momentum from the photon? Thank you!