Research Projects

We propose here a strategy to develop intense near-infrared emitting molecules through minimal functionalization of an inherent red-emitter. The process of expanding or extending a small molecule over multiple steps to achieve NIR emission is synthetically challenging and often leads to weaker intensity. Instead, we believe that minimally functionalizing an inherently red-emitting rigid molecular structure will be a more effective approach. Moreover, if we can effectively harvest as well the triplet states generated during the photoexcitation of these molecules, it will further enhance the emission intensity. Our plan is to use terrylene diimide as the basic scaffold and functionalize it with heavier chalcogen-containing heterocycles. Preliminary results indicate that this strategy successfully produces strong emission in the NIR region. Additionally, thanks to the spin-orbit coupling that facilitates intersystem crossing, some of these molecules exhibit thermally activated delayed fluorescence (TADF) and room temperature phosphorescence. The successful development of appropriate precursors recently by the PI’s group paves the way for developing novel tailor-made molecules with interesting chiroptical properties. As the strategy supports designing chiral TDI derivatives, some of the molecules can show circularly polarised luminescence in the NIR region, which is comparatively less-explored. Additionally, we propose to develop Bi(III) complexes of TDI for exploring the delayed emission behaviour.