Multifunctional Photonic Molecular Logic Gate Based On A Biphotochromic Dyad With Reduced Energy Transfer

Using molecular logic gates (MLGs) for information processing attracts attention due to perspectives of creating molecular computers. Biphotochromic dyads are suitable models of photonic MLGs. However, they suffer from one weakness: the activity of one of the photochromes is often quenched because of Förster resonance energy transfer (FRET). Herein, we designed a dyad with reduced FRET, in which both photochromes keep their photoactivity thanks to spectral and spatial separation, allowing MLG switching between different states. This novel dyad reproduces the functionality of the full set of 16 two‐input gates, as well a reversible gate–dual inverter, all gates are photonic. Less quenching—more logic: we demonstrate a biphotochromic dyad functioning as a fully photonic molecular gate, in which 1/3 of one photochrome (styrylpyridine) remaining in a non‐quenched state coupled with reactivity of the second photochrome (benzomerocyanine) being sufficient for the dyad to operate. The novel dyad reproduces the functions of all possible (16) two‐input‐one‐output gates, as well as that of a reversible gate–dual inverter