Answer to Question #124885 in Physics for kashaf

Question

What do you mean by radiative and non radiative transitions? Illustrate the electronic states of molecules and their transitions by using jablonski diagram

Answer 1

The terms radiative transition define a change of a system from one energy level to another level with emission of electromagnetic radiation. Nonradiative transition means that no energy is absorbed or emitted during the state change.

As we see in the following Jablonski diagram, a molecule has state ¹A initially. The molecule is excited to ¹A*, passes through intersystem crossing, and returns to the original state by emitting energy via phosphorescence.

Source of image: https://commons.wikimedia.org/wiki/File:JablonskiSimple.png#/media/File:JablonskiSimple.png