The structure of the blue luminescent δ-phase of tris(8-hydroxyquinoline)aluminium(<scp>iii</scp>) (Alq₃)

Abstract

The existence of the facial isomer in the delta-phase of Alq3 is proven by X-ray structural analysis, revealing that both the different molecular structure and the weaker overlap of the pi-orbitals of hydroxyquinoline ligands belonging to neighboring Alq3 molecules as compared to other phases (alpha, beta) are likely to be the origin of the significantly different optical properties of delta-Alq3.