Switching of Polymorph‐Dependent ESIPT Luminescence of an Imidazo[1,2‐<i>a</i>]pyridine Derivative

Abstract

Reproducible switching of the polymorph-dependent excited-state intramolecular proton-transfer (ESIPT) luminescence of an imidazo[1,2-a]pyridine between blue-green and yellow (see picture) is achieved by thermal control of its solid-state molecular packing. Thus, ESIPT is a promising mechanism for packing-to-luminescence transduction and amplification that offers a novel design concept for tunable organic luminescent solids.