Pressure-induced emission enhancement in 2-(anthracen-9-yl)-9 H -thioxanthen-9-one crystals with π–π stacked thioxanthone dimers

A new material, TXAN, exhibited blue-violet fluorescence under ambient pressure. Pressurization resulted in a continuous redshift of the emission peak, accompanied by a linear piezochromic behavior. A suite of high-pressure characterization techniques revealed that strengthened π-π interactions and intermolecular forces collectively suppress non-radiative transitions, enabling efficient piezochromic behavior.