CarlB said:The problem has to do with an excited atom that emits a photon. Spin doesn't contribute to the energy and so cannot provide a reason for a photon to be emitted. Intuitively, spin just doesn't get you going in the direction you need to go.
This wouldn't be the case if you were in a strong magnetic field, by the way.
Carl
Selection rules in electric dipole transitions are a set of rules that determine which transitions between energy states are allowed or forbidden. These rules are based on the conservation of energy, angular momentum, and parity.
Selection rules play a crucial role in spectroscopy as they help us understand the allowed transitions between energy states and the intensity of the spectral lines. They also provide insights into the quantum mechanical properties of atoms and molecules.
The selection rules for electric dipole transitions differ from other types of spectroscopy, such as magnetic dipole or electric quadrupole transitions. This is because each type of transition involves different conservation laws and quantum numbers.
Yes, selection rules can be violated in certain cases. This usually occurs when the selection rules are not strictly followed, or if there are additional factors influencing the transition such as external fields or interactions with other atoms or molecules.
Selection rules can be experimentally verified through spectroscopic measurements. By analyzing the intensity and polarization of spectral lines, scientists can determine which transitions are allowed and forbidden, confirming the accuracy of the selection rules.