Organic electroluminescent materials and devices

A first device comprising a first organic light emitting device, the first organic light emitting device comprising:

• an anode;
• a cathode;
• and
• an organic layer, disposed between the anode and the cathode, comprising a compound comprising a structure according to formula (I):
• wherein Cu is a monovalent copper atom;
• wherein *C is a carbene carbon,
• wherein X1 and X2 are selected from the group consisting of alkyl, cycloalkyl, alkoxy, amino, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, heteroalkynyl, arylalkyl, aryloxy, aryl, heteroalkyl, heteroaryl, and combinations thereof, or X1 and X2 optionally join to form a Ring A;
• wherein X1 and X2 are independently bonded to *C by an atom selected from the group consisting of C, N, O, S, and P,
• wherein Y is selected from the group consisting of halide, alkyl, cycloalkyl, alkoxy, amino, phosphine, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, heteroalkynyl, arylalkyl, aryloxy, aryl, heteroalkyl, heteroaryl, and combinations thereof.

A formulation comprising a compound comprising a structure according to formula (I):

• wherein Cu is a monovalent copper atom;
• wherein *C is a carbene carbon,
• wherein X1 and X2 are selected from the group consisting of alkyl, cycloalkyl, alkoxy, amino, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, heteroalkynyl, arylalkyl, aryloxy, aryl, heteroalkyl, heteroaryl, and combinations thereof, or X1 and X2 optionally join to form a Ring A;
• wherein X1 and X2 are independently bonded to *C by an atom selected from the group consisting of C, N, O, S, and P,
• wherein Y is selected from the group consisting of halide, alkyl, cycloalkyl, alkoxy, amino, phosphine, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, heteroalkynyl, arylalkyl, aryloxy, aryl, heteroalkyl, heteroaryl, and combinations thereof.