A compound having the formula Ir(LA)n(LB)3−n, having the structure




Formula I, is disclosed. In Formula I, each of Z1, Z2, Z3, and Z4 is CR2; X is O, S, or Se; n is an integer from 1 to 3; R1, R2, R3, R4, and R5 each independently represent mono- to a maximum possible number of substitutions, or no substitution; R1, R2, R3, R4, and R5 are each independently selected from a variety of substituents; any two substitutions in R1, R2, R3, R4, and R5 are optionally joined to form a ring; at least one pair of substitutions in R1, R2, R3, R4, and R5 are joined together to form a bridge structure comprising a backbone structure that forms a fused first ring, which can be further substituted; and the backbone structure is saturated. Organic light emitting devices and consumer products containing the compounds are also disclosed.