Fluorescent and Phosphorescent Species:

Molecular structure is one of the significant parameters in determining the possibility and extent of fluorescence in a chemical species. In principle, each molecule has an inherent capability to show fluorescence, thus, in reality only a few molecules actually do so. Besides structure, a fluorescent behaviour of a molecule is affected through the chemical environment in that it exists. Same the phosphorescence is also shown through a few species and there is a type of correlation along with the structure and environment. You know the phenomena of fluorescence and phosphorescence together are termed photoluminescence.