A compound including a ligand L according to Formula I: as well as, a first device and a formulation containing the same, are disclosed. In the compound including the Ligand L of Formula I: R1 and R2 are independently selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, cyano, and combinations thereof; two adjacent substituents of R1 or R2 are optionally joined to form a fused ring; ligand L is coordinated to transition metal M having an atomic number greater than 40; R1 represent mono, di, tri, or tetra-substitution, or no substitution; R2 represent mono, di, or tri-substitution, or no substitution; and at least one substituent of R1 or R2 is cyano.