Engineering hyperpolarizable coinage metal-functionalized P-flowers for next-generation photonic devices

The growing demand for advanced optoelectronic technologies has intensified the search for efficient nonlinear optical (NLO) materials for photonic and telecommunication applications. Herein, we employed a density functional theory (DFT)-based computational framework to design and evaluate coinage-metal-functionalized P-flower complexes, M@CPF (M = Cu, Ag, Au), based on the π-conjugated C₁₆(PF)₈ scaffold. The incorporation of coinage metals significantly modifies the electronic structure of CPF by promoting metal-to-framework charge transfer, reducing excitation energies, and enhancing electronic polarization. All M@CPF complexes exhibit improved polarizability and hyperpolarizability compared with pristine CPF. Among them, Ag@CPF shows the highest static first hyperpolarizability (β₀) value of 15935.63 a.u., which is 17.76 times larger than that of pristine CPF (897.31 a.u.), followed by Au@CPF and Cu@CPF. Frequency-dependent NLO analysis further reveals a remarkable dynamic response, particularly for Au@CPF, which exhibits exceptionally high first hyperpolarizability values at 1064 nm under SHG and EOPE processes. In addition, the third-order NLO response is enhanced by up to 1.68 × 10⁵ times compared with pristine CPF. UV-vis-NIR analysis confirms significant bathochromic shifts and enhanced charge-transfer transitions in the metal-functionalized complexes. These findings demonstrate that coinage-metal-functionalized P-flower architectures are promising candidates for next-generation NLO and optoelectronic applications.