Piezofluorochromic Properties and Mechanism of an Aggregation-Induced Emission Enhancement Compound Containing N-Hexyl-phenothiazine and Anthracene Moieties

A fluorescent compound, 9,10-bis(2-(10-hexyl-10H-phenothiazin-3-yl)vinyl) anthracene, has been synthesized and studied. The results show that the compound possesses piezofluorochromic properties as well as aggregation-induced emission enhancement effect. The spectroscopic properties and morphological structures are reversibly exhibited upon pressing (or grinding) or annealing (or fuming). The piezofluorochromic nature is generated through phase transformation under the stimulus of external pressure. The reason for the phase transformation caused by external pressure is ascribed to the twisted conformation of the molecule which leads to poor solid molecular packing and weak interactions in the interfaces of lamellar layers confirmed by its single-crystal X-ray diffraction analysis.