Protonation ILCT emission quenching

There are heterocyclic-substituted platinum 1,2-enedithiolates that have ILCT emissions that are either enabled by protonation of the ground state or quenched by protonation of the excited states. Which process is operative is dependent on the heterocycle appended to the 1,2-enedithiolate, and hence the electron affinity of the accepting orbital in the ILCT transition (see Fig. 2). 

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