Advancing Optoelectronics with Benzonitriles: Theoretical Understanding, Experimental Realization, and Single‐Molecule White Light Emission

Abstract Benzonitrile derivatives (BDs) are very promising for applications in materials science, photonics, and optoelectronics due to their intriguing electronic and optical properties. This study comprehensively investigates BDs, aiming to uncover their fundamental characteristics and potential applications. Using advanced theoretical techniques like Gaussian software, it is gained unprecedented insights into the photoinduced isomerization phenomenon for all‐optical switching in these compounds. The theoretical framework clarifies molecular transition states and explores a range of properties, providing a comprehensive understanding of BDs. Empirical data on the emission properties of BDs, from fluorescence analyses in liquid solutions to light amplification in solid‐state PMMA thin films, complement the theoretical examinations. Notably, white light emission from a single benzonitrile compound is achieved, showcasing its potential for data transmission through Li‐Fi technology. Finally, the all‐optical switching phenomenon in BDs using 3rd order nonlinear optical effects is experimentally validated. This complementary and comprehensive study advances understanding of BDs and demonstrates their potential for practical applications in emerging photonic and optoelectronic technologies.