Investigation of Aggregation-Induced Emission Mechanism of a Styrene Derivative: A Theoretical Unraveling of S₁/S₀‑Conical Intersection.

ABSTRACT: The mechanisms behind the fluorescence quenching of the styrene derivative, 4-dimethylamino-2-benzylidene malonic acid dimethyl ester (BIM) in solution are investigated computationally in the present study. Utilizing a penalty-constrained search algorithm of geometry optimization along with spin-flip long-range corrected time-dependent density functional theory (SF-LC-TDDFT), we examined the energetic and structural changes of the BIM molecule at the minimum energy conical intersection (MECI) between S₁ and S₀ states. Our results reveal that the S₁ excited state approaches the MECI through simultaneous rotation of the α-bond and the pyramidalization of the ethylenic CC bond. Notably, the S₁-S₀ energy gap at MECIs are 1.83 and 9.26 kJ/

SUBMITTER: Aarzoo 

PROVIDER: S-EPMC12593042 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature