A novel formalism to characterize the degree of unsaturation of organic molecules

The existing formalism to calculate the degree of unsaturation from the mol ecular formula of organic molecules cannot be applied to charged and/or dis connected species. Moreover, the calculated value depends on the assumed fo rmal valence of each of the elements. In this work, we introduce a new form alism that eliminates these problems. The suggested property, degree of uns aturation, can be calculated from the molecular formula as well as from any structural representation of a molecule corresponding to that molecular fo rmula.