In this work, we investigated the fluorescence mechanism of the probe (E)-3-((4-(diethylamino)-2-hydroxybenzylidene)amino)-2,3-dihydrothiophene-2-carboxamide (DHADC) for both Zn²⁺ and CN⁻ by using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. Utilizing the constructed potential energy curves both in the ground and excited states as a function of the distance of N2···H1, the proton transfer process of DHADC has been explored. According to the calculated spectra, another more reasonable structure of DHADC-CN for the product of DHADC responding to CN⁻ has been proposed. All of the simulated absorption and emission spectra in this work are in agreement well with those in the experiment. Furthermore, the excited state decay picture and the fluorescence quenching mechanism of DHADC, as well as the fluorescence mechanism for Zn²⁺ and CN⁻ have been fully explored.

在这项工作中，我们研究了探针 (E)-3-((4-(diethylamino)-2-hydroxybenzylidene)amino)-2,3- dihydrothiophene -2-carboxamide ( DHADC ) 对 Zn ²⁺的荧光机制和 CN ^-通过使用密度泛函理论 (DFT) 和瞬态 DFT (TD-DFT) 方法。利用构建的基态和激发态势能曲线作为 N2…H1 距离的函数，探讨了DHADC的质子转移过程。根据计算的光谱，DHADC响应CN的产物的另一个更合理的DHADC-CN结构^-已提出。本工作中的所有模拟吸收和发射光谱与实验中的一致。此外，DHADC的激发态衰变图和荧光猝灭机制，以及Zn ²⁺和CN ^-的荧光机制已得到充分探索。