Universal Display Corporation
ORGANIC ELECTROLUMINESCENT MATERIALS AND DEVICES

Abstract:

A compound including ligand L.sub.A of Formula I, ##STR00001## where L.sub.A includes at least one deuterium atom is provided. In Formula I, moiety A and B are monocyclic rings or polycyclic fused rings; K.sup.1 and K.sup.2 are direct bond, O, or S; and either (1) two R.sup.A or two R.sup.B substituents are joined together to form a fused ring structure of Formula II, ##STR00002## where Formula II is joined to ring A or ring B, respectively, by the dashed lines, and Y is Se or GeR'R''; or (2) at least one R.sup.A or R.sup.B comprises a structure of Formula III, ##STR00003## and Y is Se or GeR'R''; where Formula III is not fused to either of ring A or ring B. Formulations, OLEDs, and consumer products including the compound are also provided.