A compound comprising a ligand L.sub.A, having a structure of Formula I,

##STR00001##

is provided. In Formula I, A.sup.1 to A.sup.8 are each independently CR or N; at least two adjacent ones of A.sup.1 to A.sup.8 are CR and the Rs are joined together to form a six-membered ring fused to ring A or ring C; X is O, S, or Se; each R and R.sup.B is independently hydrogen or a substituent; any adjacent substituents are optionally joined or fused into a ring; the ligand L.sub.A is coordinated to a metal M; the metal M is bonded to ring A through a M-C bond; the metal M can be coordinated to other ligands; and the ligand L.sub.A is optionally linked with other ligands. Formulations, OLEDs, and consumer products containing such compounds are also disclosed.

A compound having the formula Ir(L.sub.A).sub.n(L.sub.B).sub.3−n, having the structure ##STR00001##
Formula I, is disclosed. In Formula I, each of Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 is CR.sup.2; X is O, S, or Se; n is an integer from 1 to 3; R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 each independently represent mono- to a maximum possible number of substitutions, or no substitution; R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are each independently selected from a variety of substituents; any two substitutions in R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are optionally joined to form a ring; at least one pair of substitutions in R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 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.

A condensed cyclic compound represented by Formula 1 and including 9 to 60 aromatic rings: ##STR00001##
A is a group represented by Formula 10, n is selected from 1, 2, 3, and 4, L is hydrogen, a single bond or a linking group, and when n is 1, p is selected from 1, 2, 3, and 4, and q is selected from 1, 2, 3, and 4, ##STR00002## wherein Formula 10 is the same as described in the specification.

A compound comprising a first ligand L.sub.A of Formula I, ##STR00001##
is disclosed. In the structure of Formula I, ring A is a 5-membered or 6-membered carbocyclic or heterocyclic ring; Z.sup.1-Z.sup.4 are each independently C or N; at least two consecutive Z.sup.1-Z.sup.4 are C, and are fused to a structure of Formula II ##STR00002##
or Formula III ##STR00003##
Y.sup.1; Y.sup.1 and Y.sup.2 are each independently O, S, Se, CRR′, SiRR′, or GeRR′; each R.sup.A, R.sup.B, R.sup.C, R, and R′ is a hydrogen or a substituent; and any two substituents may be joined or fused together to form a ring. In the compound, L.sub.A is complexed to a metal M by the dashed lines in Formula I to form a five-membered chelate ring, and M has an atomic weight greater than 40. Organic light emitting devices and consumer products containing the compounds are also disclosed.

A composition is disclosed that includes a first compound capable of functioning as a host in an emissive layer of an OLED at room temperature; and a second compound that includes a ligand L.sub.A of Formula III ##STR00001##
where ring A is a 5-membered or 6-membered carbocyclic or heterocyclic ring; where R represents two adjacent substituents that are joined together to form a ring that is fused to ring B, and R has a structure of Formula IV ##STR00002##
or Formula V ##STR00003##
disclosed herein.

Embodiments of the disclosed subject matter provide a full-color pixel arrangement for a device, the full-color pixel arrangement including a plurality of sub-pixels, each having an emissive region of a first color, where the full-color pixel arrangement comprises emissive regions having exactly one emissive color that is a red-shifted color of a deep blue sub-pixel of the plurality of sub-pixels. Embodiments of the disclosed subject matter may also provide a full-color pixel arrangement for a device, the full-color pixel arrangement including a plurality of sub-pixels, each having an emissive region of a first color, where the full-color pixel arrangement comprises emissive regions having exactly one emissive color, and where the plurality of sub-pixels comprise a light blue sub-pixel, a deep blue sub-pixel, a red sub-pixel, and a green sub-pixel.

A heterocyclic compound, a composition including the heterocyclic compound, and an organic light-emitting device including the heterocyclic compound are disclosed. The heterocyclic compound is represented by Formula 1: ##STR00001##
wherein, X.sub.1, L.sub.1, a1, Ar.sub.1, R.sub.1 to R.sub.6, b3, b4, and b5 are described herein.

A compound is disclosed that is selected from the group consisting of a structure having Formula I ##STR00001##
and a structure having Formula II ##STR00002##

Provided are an organometallic compound represented by Formula 1 and an organic light-emitting device including the same. The organic light-emitting device includes a first electrode; a second electrode facing the first electrode; an organic layer between the first electrode and the second electrode and including an emission layer; and at least one organometallic compound represented by Formula 1.

An organometallic compound represented by Formula 1:

M(L.sub.1).sub.n1(L.sub.2).sub.n2  Formula 1

wherein, M is a transition metal, L.sub.1 and L.sub.2 are ligands as provided herein, n1 and n2 are each independently 1 or 2, the sum of n1 and n2 is 2 or 3, and L.sub.1 is different from L.sub.2.