A rotational transition is an abrupt change in angular momentum in quantum physics. Like all other properties of a quantum particle, angular momentum is quantized, meaning it can only equal certain discrete values, which correspond to different rotational energy states. When a particle loses angular momentum, it is said to have transitioned to a lower rotational energy state. Likewise, when a particle gains angular momentum, a positive rotational transition is said to have occurred.
Rotational transitions are important in physics due to the unique spectral lines that result. Because there is a net gain or loss of energy during a transition, electromagnetic radiation of a particular frequency must be absorbed or emitted. This forms spectral lines at that frequency which can be detected with a spectrometer, as in Rotational spectroscopy or Raman spectroscopy.
Famous quotes containing the word transition:
“The most remarkable aspect of the transition we are living through is not so much the passage from want to affluence as the passage from labor to leisure.... Leisure contains the future, it is the new horizon.... The prospect then is one of unremitting labor to bequeath to future generations a chance of founding a society of leisure that will overcome the demands and compulsions of productive labor so that time may be devoted to creative activities or simply to pleasure and happiness.”
—Henri Lefebvre (b. 1901)