Mechanochromic luminescence and aggregation induced emission for a metal-free β-diketone†
Reversible mechanochromic luminescence (ML) is known for difluoroboron β-diketonates (BF2bdks). Here, we report ML for the methoxy-substituted dinaphthoylmethane (dnmOMe) ligand even without coordination to boron. In addition, dnmOMe shows solvatochromism and aggregation-induced emission (AIE). Diketone thin films showed high contrast emission when smeared, and rapid recovery of the pre-smeared state at room temperature.