What are the consequences of Light Absorption?
According to the principle of photochemical activation, only that part of the light which is absorbed by any system can cause photochemical change or reaction. However this is not essential that every time, the energy which is absorbed by any system can bring about a photochemical reaction. Also the light absorbed by any system may be re-emitted almost at the same time, either in one step or in more steps. This phenomenon is called fluorescenes. Also sometimes the light absorbed by any system may re-emit the energy slowly or even after the removal of source light, this phenomenon is called phosphorescenes. Process of Fluorescenes, phosphorescenes is best explained with the help of Jablonski diagram. In order to understand the diagram, we have considered some terminology. As most molecules contain even number of electrons hence they are in ground state, also all the electrons are paired with other electrons. The equation 2S+1, where S is known as the spin multiplicity means total number
