A compound is represented by a formula (1) below, in which k is an integer of 0 or more, m is an integer of 1 or more, n is an integer of 2 or more. L is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, CN is a cyano group, and D.sub.1 and D.sub.2 are each independently represented by one of a formula (2), a formula (3) and formula (3x) below, D.sub.1 and D.sub.2 being optionally mutually the same or different.

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A compound is represented by a formula (1) below, in which k is an integer of 0 or more, m is an integer of 1 or more, n is an integer of 2 or more. L is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, CN is a cyano group, and D.sub.1 and D.sub.2 are each independently represented by one of a formula (2), a formula (3) and formula (3x) below, D.sub.1 and D.sub.2 being optionally mutually the same or different.

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There is disclosed a compound Formula I

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In Formula I: Z is CR.sup.4R.sup.5, C═CR.sup.4R.sup.5, SiR.sup.4R.sup.5, GeR.sup.4R.sup.5, NR.sup.4a, PR.sup.4a, P(O)R.sup.4a, O, S, SO, SO.sub.2, Se; SeO, SeO.sub.2, Te, TeO, or TeO.sub.2; R.sup.1 - R.sup.3 are the same or different at each occurrence and are D, aryl, heteroaryl, alkyl, amino, silyl, germyl, deuterated aryl, deuterated heteroaryl, deuterated alkyl, deuterated amino, deuterated silyl, or deuterated germyl, where two groups selected from R.sup.1, R.sup.2, and R.sup.3 can be joined together to form a fused ring; R.sup.4 - R.sup.5 are the same or different at each occurrence and are H, D, aryl, heteroaryl, alkyl, amino, silyl, germyl, deuterated aryl, deuterated heteroaryl, deuterated alkyl, deuterated amino, deuterated silyl, or deuterated germyl; R.sup.4a is alkyl, silyl, germyl, aryl, or a deuterated analog thereof; a is an integer from 0-4; b and c are the same or different and are an integer from 0-3.

There is disclosed a compound Formula I

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In Formula I: Z is CR.sup.4R.sup.5, C═CR.sup.4R.sup.5, SiR.sup.4R.sup.5, GeR.sup.4R.sup.5, NR.sup.4a, PR.sup.4a, P(O)R.sup.4a, O, S, SO, SO.sub.2, Se; SeO, SeO.sub.2, Te, TeO, or TeO.sub.2; R.sup.1 - R.sup.3 are the same or different at each occurrence and are D, aryl, heteroaryl, alkyl, amino, silyl, germyl, deuterated aryl, deuterated heteroaryl, deuterated alkyl, deuterated amino, deuterated silyl, or deuterated germyl, where two groups selected from R.sup.1, R.sup.2, and R.sup.3 can be joined together to form a fused ring; R.sup.4 - R.sup.5 are the same or different at each occurrence and are H, D, aryl, heteroaryl, alkyl, amino, silyl, germyl, deuterated aryl, deuterated heteroaryl, deuterated alkyl, deuterated amino, deuterated silyl, or deuterated germyl; R.sup.4a is alkyl, silyl, germyl, aryl, or a deuterated analog thereof; a is an integer from 0-4; b and c are the same or different and are an integer from 0-3.

Provided are a compound for an organic optoelectronic device represented by Chemical Formula 1, a composition for an organic optoelectronic device including the same, an organic optoelectronic device, and a display device. The content of Chemical Formula 1 is as defined in the specification.

Provided are a compound for an organic optoelectronic device represented by Chemical Formula 1, a composition for an organic optoelectronic device including the same, an organic optoelectronic device, and a display device. The content of Chemical Formula 1 is as defined in the specification.

A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer disposed between the first electrode and the second electrode, the interlayer including an emission layer. The emission layer includes a first emission layer including a first host and a second host, and a second emission layer including a third host. A triplet energy T.sub.1_H1 of the first host, a triplet energy T.sub.1_H2 of the second host, and a triplet energy T.sub.1_H3 of the third host satisfy Formulae (1) and (2) as defined below:

T.sub.1_H1−T.sub.1_H3≥0.2 eV  (1),

T.sub.1_H2−T.sub.1_H3≥0.2 eV  (2).

A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer disposed between the first electrode and the second electrode, the interlayer including an emission layer. The emission layer includes a first emission layer including a first host and a second host, and a second emission layer including a third host. A triplet energy T.sub.1_H1 of the first host, a triplet energy T.sub.1_H2 of the second host, and a triplet energy T.sub.1_H3 of the third host satisfy Formulae (1) and (2) as defined below:

T.sub.1_H1−T.sub.1_H3≥0.2 eV  (1),

T.sub.1_H2−T.sub.1_H3≥0.2 eV  (2).

Provided is an organic light emitting device comprising an anode; a cathode; and a light emitting layer between the anode and the cathode, wherein the light emitting layer comprises a compound of the following Chemical Formula 1 and a compound of the following Chemical Formula 2:

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where A′ is a naphthalene ring fused with an adjacent ring and is unsubstituted or substituted with deuterium, and the other substituents are described in the specification. Organic light emitting devices in which a compound of Chemical Formula 1 and a compound of Chemical Formula 2 are co-deposited as a host for a light emitting layer exhibit reduced driving voltage and increased efficiency and lifespan.

Provided is an organic light emitting device comprising an anode; a cathode; and a light emitting layer between the anode and the cathode, wherein the light emitting layer comprises a compound of the following Chemical Formula 1 and a compound of the following Chemical Formula 2:

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where A′ is a naphthalene ring fused with an adjacent ring and is unsubstituted or substituted with deuterium, and the other substituents are described in the specification. Organic light emitting devices in which a compound of Chemical Formula 1 and a compound of Chemical Formula 2 are co-deposited as a host for a light emitting layer exhibit reduced driving voltage and increased efficiency and lifespan.