Universal Display Corporation
Organic electroluminescent materials and devices

Abstract:

Heteroleptic iridium complexes having the formula ##STR00001## are disclosed. In this formula, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6, are selected from hydrogen, deuterium, cycloalkyl, deuterated cycloalkyl, alkyl, and deuterated alkyl, and can optionally be linked together to form a ring; at least one of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 is cycloalkyl, deuterated cycloalkyl, alkyl, or deuterated alkyl; ring A is attached to the 4- or 5-position of ring B; and R and R' can represent any of a variety of subsitutents. These iridium compounds contain alkyl substituted phenylpyridine ligands, which provide these compounds with beneficial properties when the iridium complexes are incorporated into OLED devices.