Universal Display Corporation
Organic electroluminescent materials and devices

Abstract:

A method of making an osmium(II) complex having Formula I, L.sup.1-Os-L.sup.2, wherein L.sup.1 and L.sup.2 are independently a biscarbene tridentate ligand, wherein L.sup.1 and L.sup.2 can be same or different is disclosed. The method includes (a) reacting a precursor of ligand L.sup.1 with an osmium precursor to form an intermediate product, wherein the osmium precursor having the formula OsH.sub.x(PR.sub.3).sub.y, wherein x is an integer from 2 to 6 and y is an integer from 2 to 5, and R is selected from the group consisting of aryl, alkyl and cycloalkyl; and (b) reacting a precursor of ligand L.sup.2 with said intermediate product.