Universal Display Corporation
ORGANIC ELECTROLUMINESCENT MATERIALS AND DEVICES

Abstract:

A compound comprising a first ligand L.sub.A having the formula ##STR00001## Formula I, is disclosed. In Formula I, ring A is a five- or six-membered carbocyclic or heterocyclic ring; Y.sup.1 is selected from carbon and nitrogen; each of X.sup.1 to X.sup.4 is C or N; at least two adjacent R.sup.2s of ring B form a fused structure having the following formula: ##STR00002## ring C is fused to ring B and the wavy lines are bonds attached to ring B; ring D and ring E are either a 5-membered aromatic ring or a 6-membered aromatic ring; each R.sup.1, R.sup.2, R.sup.3, R.sup.A, R.sup.B, R.sup.C, and R.sup.D is independently selected from a variety of substituents; ligand L.sub.A is coordinated to a metal M and, optionally, linked with other ligands; and M is optionally coordinated to other ligands. Organic light emitting devices and consumer products containing the compounds are also disclosed.