Thermotriggered Domino-like Single-Crystal-to-Single-Crystal Phase Transition from Face-to-Edge to Face-to-Face Packing of Anthracenes.

Stimuli-triggered crystal-to-crystal and single-crystal-to-single-crystal (SCSC) transformations have received significant attention in the scientific community. To visualize such phenomenon, controlling the optical properties and the thermodynamic stability of the molecular crystals is a very important research subject. In this report, the selective growth of photoluminescent (PL) 1,8-bisphenylanthracene polymorphic (cI and cII) and 1,2-dichloroethane-inclusion crystals (iC) under various optimized conditions is described. These crystals exhibited unique mechano- and thermoresponsive disordering, crystal-to-crystal phase transition, and SCSC phase transition. In particular, rapid thermostimulus SCSC occurred from blue-PL cI into greenish-blue-PL cII. Interestingly, the SCSC phase transition of cI into cII was triggered by thermal stimuli and propagated spontaneously. Thermotriggered domino-like SCSC phase transition was observed on a fully visible timescale (ca. 125 μm min-1 ).