In this study, a hemicyanine dye, trans‐4‐(4‐(diethylamino)styryl)‐1‐ethylpyridinium bromide (DYE‐BD), was synthesised and simulated. The maximum absorption wavelength of DYE‐BD was calculated with the same basis set by using the Gaussian 09 software based on different methods, while time‐dependent density functional theory was applied to simulate the maximum emission wavelength of the designed dye. The changes in enthalpy and Gibbs free energy were simulated at the b3lyp/6‐31G(d) level, and energy changes in the luminescence process were assessed using mathematical methods. Furthermore, DYE‐BD was used to colour acrylic fabric following the typical dyeing procedure for cationic dyes. The photostability of the synthesised dye was analysed using quantum theory and mathematical methods. The synthesised dye, analysed using the Ecological Structure Activity Relationships class program, had no toxicity to aquatic life, while the acrylic fabrics dyed with DYE‐BD met the fluorescent orange requirements for background and combined performance materials according to the EN ISO 20471:2013 standard.

中文翻译：

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荧光半菁染料的模拟，合成，表征和染色性能

在这项研究中，合成并模拟了半花青染料反式4-（4-（二乙氨基）苯乙烯基）-1-乙基溴化吡啶鎓（DYE-BD）。通过使用高斯09软件，基于不同的方法，以相同的基准集计算出DYE-BD的最大吸收波长，同时应用了时变密度泛函理论来模拟设计染料的最大发射波长。在b3lyp / 6-31G（d）水平上模拟了焓和吉布斯自由能的变化，并使用数学方法评估了发光过程中的能量变化。此外，按照阳离子染料的典型染色步骤，DYE-BD用于对丙烯酸织物进行染色。使用量子理论和数学方法分析了合成染料的光稳定性。合成染料