Universal Display Corporation
Organic electroluminescent materials and devices

Abstract:

A compound having a formula M(L.sub.A)(L.sub.B)(L.sub.C) is described. In formula M(L.sub.A)(L.sub.B)(L.sub.C), ligands L.sub.A and L.sub.B are each a mono-anionic bidentate ligand coordinated to metal M forming a 5-member cyclometalated ring and ligands L.sub.A and L.sub.B are covalently linked by a linking group. There is at least one loop of M-L.sub.A-linking group-L.sub.B-M having only arylene or heteroarylene groups in the loop other than M. In the compound, each ring in the linking group is part of a backbone of the loop; and either (i) the loop comprises a specific DBX moiety and the linking group comprises two or more arylene or heteroarylene groups, or (ii) the linking group comprises three or more arylene or heteroarylene groups. Formulations, OLEDs, and consumer product containing the compound are also disclosed.