Impact of Substitution Position on the Excited‐State Dynamics and Nonlinear Optical Properties of Tetraphenylethylene‐Corroles

Investigating the structure–property relationship in π‐conjugated organic materials is crucial for designing efficient materials for diverse optoelectronic applications. Tailoring the molecular structure enables tuning the nonlinear optical (NLO) properties of π‐conjugated systems. Herein, we report the synthesis, characterization, and photophysical properties of tetraphenylethylene (TPE)‐substituted corroles in meso ( meso‐TPE‐Cor ) and beta position ( β‐TPE‐Cor ). The excited state dynamics, investigated using femtosecond transient absorption spectroscopy (fs‐TAS) with excitation at the Soret band (400 nm), revealed an internal conversion in the 250–303 fs range, vibrational relaxation (VR) in 7.1–12.7 ps range, an intersystem crossing (ISC) in 0.94–1.05 ns range, and the triplet lifetime in 0.111–0.126 µs range. Comparatively, β‐TPE‐Cor exhibited faster ISC and VR than meso‐TPE‐Cor . Furthermore, the NLO properties of both the corroles were investigated using the femtosecond Z‐scan technique. Both the corroles exhibited significantly strong NLO parameters, characterized by prominent three‐photon absorption (3PA) coefficients (∼10 −4 cm 3 /GW 2 ), high nonlinear refractive index ( n 2 ∼10 −14 cm 2 /W), and hyperpolarizabilities (γ ∼ 10 −30 esu). We observed that substituting the same TPE substituent in the β position demonstrated better NLO properties. Furthermore, as a proof‐of‐concept application, we investigated the optical limiting onset threshold of both the corroles, which exhibited superior performance compared to previously reported organic materials, highlighting its application in various photonic devices.