Singlet state overview

An overview of the energetics and possible depletion mechanisms of excited electronic states is named a Jablonski diagram. Herein, singlet states are symbolized by So, Si, S2, and so on, and triplets by T0, Ti, T2, and so on, where the index labels their energetic order and should not be confused with tensor components. A typical Jablonski diagram for an organic molecule is shown in Figure 19. 

The present review summarizes some of the recent results obtained in theoretical studies of pristine and oxidized graphene substrates. It shows that global and local delocalization effects can be seen as a common grounds for explanation of certain peculiar properties of these systems. In the former case it leads to a rationale for the origin of stabilization of diradical singlet states and in the latter case it provides a very simple and intuitive perspective on relative stability of oxyradicals formed. Before discussing these findings in details, it is useful to overview pertinent approaches to the assessment of aromaticity. 

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