A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula 1 or Formula II, where M is platinum or palladium.

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The present specification relates to a heterocyclic compound represented by Chemical Formula 1, an organic light emitting device comprising the same, and a composition for an organic material layer of an organic light emitting device.

A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula I or Formula II, where M is platinum or palladium.

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Compounds comprising phosphorescent metal complexes comprising cyclometallated imidazo[1,2-f]phenanthridine and diimidazo[1,2-a:1,2-c]quinazoline ligands, or isoelectronic or benzannulated analogs thereof, are described. Organic light emitting diode devices comprising these compounds are also described.

This invention relates to compounds containing heterocycles or azaheterocycles and phenylene or azaphenylene wherein at least one ring is a five-membered ring. These novel compounds are useful as host materials for phosphorescent electroluminescent devices.

An organometallic compound represented by Formula 1, a light-emitting device including the same, and an electronic apparatus including the light-emitting device are disclosed. In Formula 1, the substituents are as described in more detail in the specification. ##STR00001##

An organic light emitting device having an anode; an emissive region; and a cathode is provided. The emissive region can be disposed between the anode and the cathode. The emissive region can include a first compound, D1, which is a first metal complex; and a second compound, D2, which is a second metal complex, where D1 and D2 are different. The emission from the OLED does not primarily originate from D2 or from an exciplex between D1 and D2, the emission from the OLED has an emission peak maximum between 300 to 2000 nm; and, when the emission from the OLED has a peak between 550 and 700 nm, then D2 is not a Be, Al, or Ir complex. Consumer products containing the OLED are also provided.

A compound of Formula I,

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is provided. In Formula I, M is Pt or Pd; moieties B, C, and D are independently a monocyclic ring or a polycyclic fused ring system; moiety E is a monocyclic ring or a bicyclic fused ring system; n is 0, 1, or 2; K and K.sup.1 to K.sup.3 are independently a direct bond or a linker; Z is C or a heteroatom; each of Z.sup.1 to Z.sup.3 is independently C or N; X is CR, CRR, NR, or PRR; each of X.sup.C, X.sup.D, X.sup.1 to X.sup.3 and X.sup.8 to X.sup.12 is independently C or N; L.sup.1 is a direct bond or a linker; L.sup.2 is absent a bond, a direct bond, or a linker; each of Q.sup.1 and Q.sup.2 is a direct bond or a linker; each R substituent is independently hydrogen or a General Substituent. Formulations, OLEDs, and consumer products containing the same are also provided.

Fluorene derivatives that are connected in one or more of the 1-, 1-, 4-, or 4-positions in any combination to a carbon atom of a diaryl substituted triazinyl or pyrimidinyl derivative. The fluorene derivatives are not spirobifluorene derivatives. The compounds are suitable for use in electronic devices, in particular organic electroluminescent devices, comprising these compounds. In some embodiments, the compounds are used as matrix materials for phosphorescent or fluorescent emitters as well as a hole-blocking or an electron-transport layer.

A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula 1 or Formula II, where M is platinum or palladium. ##STR00001##