A carbazole containing triphenylethylene derivative (TrPEBCar) has been designed and synthesized, which combines aggregation-induced emission (AIE), piezochromism and photochromism together. In the crystalline state, an intensive emission band at 448 nm was detected. After pressing the crystalline solid, a [crystalline–amorphous] morphological transition takes place, in which the resulting amorphous state of TrPEBCar exhibits a different color and a red-shifted emission band at 470 nm. Photochromic behavior of TrPEBCar is achieved by utilizing a stilbene-type intramolecular photocyclization in the crystalline state. In addition, we report for the first time morphology-dependent photochromism, in which the photochromic properties of TrPEBCar are only observed in the crystalline state but not in the amorphous state. Therefore, the methods of pressing/fuming and heating/fuming act as gates to switch the photochromic properties by changing the aggregation states between the crystalline and amorphous states. By combining the piezochromic properties with the photochromic properties, the ON/OFF states of TrPEBCar can easily be observed by the different colors and emission properties. The triphenylethylene derivative with simple molecular structure provides a new approach for gated photochromic materials with both switch and indicator.

中文翻译：

---

通过在AIE活性分子中将光致变色和压致变色结合在一起的一种可转换光致变色材料的新方法†

设计并合成了一种含咔唑的三苯乙烯衍生物（TrPEBCar），它将聚集诱导发射（AIE），压致变色和光致变色结合在一起。在结晶状态下，检测到在448nm的强发射带。压制结晶固体后，发生[结晶-无定形]形态转变，其中所得的TrPEBCar非晶态表现出不同的颜色，并在470 nm处出现红移发射带。TrPEBCar的光致变色行为是通过利用处于结晶状态的二苯乙烯型分子内光环化来实现的。此外，我们首次报道了形态相关的光致变色现象，其中仅在结晶状态下观察到TrPEBCar的光致变色特性，而在非晶态下观察不到。所以，压制/发烟和加热/发烟的方法通过改变结晶态和非晶态之间的聚集态而充当切换光致变色特性的门。通过将压致变色性质与光致变色性质相结合，可以通过不同的颜色和发射性质轻松地观察到TrPEBCar的ON / OFF状态。具有简单分子结构的三苯基乙烯衍生物为带有开关和指示器的门控光致变色材料提供了一种新方法。