Universal Display Corporation
Organic electroluminescent materials and devices

Abstract:

A compound having the formula Ir(L.sub.A).sub.n(L.sub.B).sub.3-n, having the structure ##STR00001## of Formula I is provided. In the structure of Formula I, each of A.sup.1 through A.sup.8 is independently carbon or nitrogen; at least one of A.sup.1 through A.sup.8 is nitrogen; ring B is bonded to ring A through a C--C bond; the iridium is bonded to ring A through an Ir--C bond; X is O, S, or Se; each of R.sup.1 through R.sup.5 are independently selected from a variety of substituents, which may be linked to form a ring; n is an integer from 1 to 3; and at least one R.sup.2 adjacent to ring C is not hydrogen. Formulations and devices, such as OLEDs, that include the first compound are also provided.