STRUCTURE–PROPERTY ANALYSIS OF D–Π–A NAPHTHALENE CHROMOPHORES FOR OPTOELECTRONIC APPLICATIONS

Abstract

Donor–π–acceptor chromophores are an important class of organic functional materials because their optical and electronic properties can be tuned through molecular design. In these systems, an electron-donating group and an electron-accepting group are connected through a conjugated π-bridge, enabling intramolecular charge transfer after excitation. Naphthalene is a suitable structural platform for such chromophores because of its rigid aromatic framework, chemical stability, extended conjugation and multiple substitution sites. The present article examines the relationship between molecular structure and optoelectronic behaviour in D–π–A naphthalene chromophores. The analysis focuses on donor and acceptor strength, π-conjugation, substitution pattern, molecular planarity, solvent polarity, aggregation, frontier molecular orbitals and nonlinear optical response. The study indicates that efficient optoelectronic performance depends on a balanced relationship among charge transfer, molecular rigidity, orbital overlap, fluorescence efficiency, thermal stability and solid-state packing. Extended conjugation generally shifts absorption towards longer wavelengths and narrows the optical energy gap, but excessive flexibility and aggregation may increase non-radiative losses. The article proposes an integrated experimental and computational methodology for designing and evaluating naphthalene chromophores for organic light-emitting devices, fluorescence sensing, photovoltaics, nonlinear optics and molecular electronics.