A compound having the following formula: wherein M is a metal selected from the group consisting of Ir, Pt, Pd, Rh, Re, Ru and Os; C-N is a substituted or unsubstituted cyclometallated ligand, and (C-N) is different from at least one other ligand attached to the metal; wherein at least one ligand functions as a phosphorescent emissive ligand in the compound at room temperature and at least one ligand does not function a phosphorescent emissive ligand in the compound at room temperature: wherein the emissive ligand in the compound at room temperature has a triplet energy corresponding to a wavelength that is at least 80 nm greater than the wavelength corresponding to the triplet energy of a ligand that is not emissive in the compound at room temperature; wherein each of R 8 and R 11 to R 14 is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2, NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; X is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2 NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; additionally or alternatively, any two adjacent substituted positions together form, independently, a fused 4-to 7-member cyclic group, which may be cycloalkyl, cycloheteroalkyl, aryl, or heteroaryl, and the 4-to 7-member cyclic group may be further substituted with substituent X Z is selected from -CH 2 -,-CRR-, -NH, NR, -O, -S, SiR; each R is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2, NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; and m has a value of at least 1; n has a value of at least 1; and m+n is the maximum number of ligands that may be attached to the metal, and wherein alkyl is a straight or branched chain alkyl radical having 1 to 15 carbon atoms and which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR; wherein alkenyl is a straight or branched chain alkene radical containing 2 to 15 carbon atoms which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR; wherein alkynyl is a straight or branched chain alkyn radical containing 2 to 15 carbon atoms and which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR. M is a metal selected from the group consisting of Ir, Pt, Pd, Rh, Re, Ru and Os; C-N is a substituted or unsubstituted cyclometallated ligand, and (C-N) is different from at least one other ligand attached to the metal; wherein at least one ligand functions as a phosphorescent emissive ligand in the compound at room temperature and at least one ligand does not function a phosphorescent emissive ligand in the compound at room temperature: wherein the emissive ligand in the compound at room temperature has a triplet energy corresponding to a wavelength that is at least 80 nm greater than the wavelength corresponding to the triplet energy of a ligand that is not emissive in the compound at room temperature; each of R 8 and R 11 to R 14 is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2, NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; X is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2 NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; additionally or alternatively, any two adjacent substituted positions together form, independently, a fused 4-to 7-member cyclic group, which may be cycloalkyl, cycloheteroalkyl, aryl, or heteroaryl, and the 4-to 7-member cyclic group may be further substituted with substituent X Z is selected from -CH 2 -,-CRR-, -NH, NR, -O, -S, SiR; each R is independently selected from hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, CF 3, CO 2 R, C R, NR 2, NO 2, OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; and m has a value of at least 1; n has a value of at least 1; and m+n is the maximum number of ligands that may be attached to the metal, and wherein alkyl is a straight or branched chain alkyl radical having 1 to 15 carbon atoms and which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR; wherein alkenyl is a straight or branched chain alkene radical containing 2 to 15 carbon atoms which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR; wherein alkynyl is a straight or branched chain alkyn radical containing 2 to 15 carbon atoms and which may be substituted with one or more substituents selected from halo, CN, CO 2 R, C, NR 2, cyclic amino, NO 2 and OR.