Boosting Emission Enhancement in TPTA by Pressure‐Treated Strengthened Intermolecular Interactions

Abstract The photophysical properties of luminescent materials in aggregate states are critically governed by molecular packing. Herein, the precise quantitative control of the luminescent properties in 2,4,6‐triphenyl‐1,3,5‐triazine (TPTA) crystal is achieved by modulating pressure. Notably, the TPTA crystal exhibits a pronounced enhanced PL intensity at 8.9 GPa, and the photoluminescence quantum yield (PLQY) has been raised 3 folds as to the initial state. Comprehensive analysis, including pressure‐dependent structural data and theoretical results, demonstrates that this pressure‐responsive behavior is attributed to the enhanced intermolecular interactions under high pressure, which restrict intramolecular vibration effectively and reduce non‐radiative loss. Above 8.9 GPa, the significantly enhanced π–π interactions become dominant, causing a decrease in PL intensity. Additionally, the continuous redshift of the emission peak is due to the increased π–π interactions and the reduction of intermolecular distances. This research successfully exerts precise manipulation over the optical characteristics of TPTA, while also delivering a thorough and systematic elucidation of the structure‐property correlations. Such insights offer significant contributions to the strategic design of functional molecules at the national level and facilitate the advancement of organic materials that exhibit pressure‐induced behaviors of enhanced emission.