Touch-sensitive mechanoluminescence crystals comprising a simple purely organic molecule emit bright blue fluorescence regardless of crystallization methods

Simple N-phenylcarbazole (NPC) could readily form brightly mechanofluorescent crystals with mechanically touch-sensitive response, regardless of crystallization methods. NPC with room-temperature photophosphorescence did not exhibit mechano-phosphorescence, signifying that the excitation modes could play an important role in affecting light-emitting processes.