Multifunctional Logic Applications of a Single Molecule: A Molecular Photo‐Switch Performing as Simple and Complex Gates, Memory Element, and a Molecular Keypad Lock

Abstract

Carbazole (CZ) can act as a photo‐switch leading to a multifunctional logic system when triggered by fluoride (F–) ions, H2O and light, through efficient interaction of the pyrrole unit with the anions. Here we are reporting a unimolecular platform of CZ (and case specific CZ‐F–) that can be configured as NOT, YES, complimentary IMPLICATION and INHIBIT, a new complex logic gate performing IF‐THEN and NOT operations and a memory element with cyclic “Erase‐Read‐Write‐Read” ability with feedback loop mechanism. The fluorescence responses of the CZ system also have been exploited to design a potential highly secured molecular keypad lock operating with a purely opto‐chemical password composed with optical and chemical input keys. The system displays the applications of light responsive molecules as multifunctional, reconfigurable molecular logic devices that may lead towards true molecular information processing units.

True-Photonic Strategy for Chemically Encrypted Two-Factor Authentication with Unlimited Chemical Passwords Based on Cascade Energy Transfer under a Single Wavelength Excitation

“…There has been a rapid advancement in the field of molecular logic devices that includes multiparameter binary logic gates, − memory elements, , other complex processors, − and most importantly, molecular security devices or chemical password protection systems. − Development of these molecular devices is primarily driven by dimension minimization, efficiency maximization/enhancement, multidimensional applications, etc. Among others, the molecular password systems might find the most critical applications as replacements of conventional electronic security devices, like in a bank ATM.…”

Doping Dopamine in Carbon Nanoparticles: A New Multifunctional Logic-Based Decision-Making Molecule

“…Operational logic gates have frequently been developed by exploiting the property of molecular fluorescence. Change in fluorescence intensity for specific sensing of metal ions has also been a suitable tool. , Alterations in temperature and pH, chemically triggered fluorescence switching, , etc. can act as inputs for the corresponding relevant outputs.…”

“…Change in fluorescence intensity for specific sensing of metal ions has also been a suitable tool. 22,23 Alterations in temperature and pH, 24 chemically triggered fluorescence switching, 25,26 etc. can act as inputs for the corresponding relevant outputs.…”