Extended pi-conjugated platinum (II) complexes

1. An organometallic complex used as a light-emitting material in an electroluminescent (EL) device, an organic light-emitting device (OLED), a polymer light-emitting device (PLED), a photovoltaic cell, a field-effect transistor, a sensor, or a laser comprising:

an extended π-conjugated tridentate ligand having a platinum center, wherein the ligand comprises an extended π-conjugated tridentate ligand having the following structures:

wherein R 1 -R 3 are independently hydrogen, halogen, hydroxyl, an unsubstituted alkyl, a substituted alkyl, cycloalkyl, aryl, acyl, alkoxy, acyloxy, amino, acylamino, aralkyl, cyano, carboxyl, thio, styryl, aminocarbonyl, carbamoyl, aryloxycarbonyl, phenoxycarbonyl, or an alkoxycarbonyl group; R 2 and R 5 can also be substituted aryl group;

wherein if the R 1 -R 6 substituents are not monovalent group(s), they can form a ring together with the group on which they are substituted;

wherein the extended nitrogen heterocyclic system independently has one of the following structures:

where R 7 -R 14 are hydrogen, halogen, hydroxyl, unsubstituted alkyl, an substituted alkyl, cycloalkyl, an aryl, acyl, alkoxy, acyloxy, amino, acylamino, aralkyl, cyano, carboxyl, thio, styryl, aminocarbonyl, carbamoyl, aryloxycarbonyl, phenoxycarbonyl, or an alkoxycarbonyl group;

where if the R 7 -R 14 substituents are not monovalent groups(s), they can form a ring together with the group on which they are substituted; and

wherein the extended aromatic systems have one of the following structures:

where R 15 -R 22 are independently hydrogen, halogen, hydroxyl, unsubstituted alkyl, substituted alkyl, cycloalkyl, aryl, acyl, alkoxy, acyloxy, amino, acylamino, aralkyl, cyano, carboxyl, thio, styryl, aminocarbonyl, carbamoyl, aryloxycarbonyl, phenoxycarbonyl, or an alkoxycarbonyl group; and

where if the R 15 -R 22 are not monovalent group(s), they can form a ring together with the group on which they are substituted.

2. The organometallic complex of claim 1 , wherein the extended π-conjugation tridentate ligand coordinates to the platinum center through two nitrogen bonds and a carbon bond, wherein the tridentate ligand bears a formal negative charge localized at a site of a metal-carbon bond, and wherein the extended π-conjugation tridentate ligand has the following chemical structure:

wherein L comprises one of the following:

(1) a negatively charged of fluoride, chloride, bromide, or iodide atom;

(2) a ligand group capable of forming a carbon metal bond in the organometallic complex, including an acetylide, an alkenyl, an unsubstituted aryl, an substituted aryl, an unsubstituted alkyl, a substituted alkyl, a cyano, a cyclopentienyl, a vinyl, an allyl, or an alkyl group; or

(3) R′E, wherein E comprises a substituent that is capable of forming a bond to platinum includes an N, O, S, or Se wherein atom and R′ is hydrogen, halogen, hydroxyl, unsubstituted alkyl, substituted alkyl, cycloalkyl, aryl, acyl, alkoxy, acyloxy, amino, acylamino, aralkyl, cyano, carboxyl, thio, styryl, aminocarbonyl, carbamoyl, aryloxycarbonyl, phenoxycarbonyl, or an alkoxycarbonyl group.

3. The organometallic complex of claim 1 , wherein the complex is being deposited using thin layer vacuum deposition.

4. The organometallic complex of claim 1 , wherein the light-emitting material is applied using spin-coating.

5. A heterostructure light-emitting device comprising:

a substrate;

a first electrode deposited over the substrate;

a first hole transporting layer;

a first emissive layer comprising a host material and an emitting/dopant complex, wherein the emitting/dopant complex is the organometallic complex of claim 1 ;

a hole blocking layer;

an electron transporting layer; and

a second electrode deposited over the electron transporting layer, sandwiching the hole transporting layer, emissive layer, hole blocking layer and electron transporting layer between the first and the second electrodes.

6. The heterostructure light-emitting device of claim 5 , further comprising:

a second hole transporting layer;

a blue emissive layer;

wherein the second electrode sandwiches the hole transporting layer, the first emissive layer, the second hole transporting layer, the blue emissive layer, the hole blocking layer and the electron transporting layer between the first and the second electrodes.

7. The heterostructure light-emitting device of claim 5 , wherein the hole transporting layer is naphthylphenylbiphenylamine (NPB), or 4,4′-bis[N,N′-3-tolylamino]-3,3′-dimethylbiphenyl (HMTPD).

8. The heterostructure light-emitting device of claim 6 , wherein the hole transporting layer is naphthylphenylbiphenylamine (NPB), or 4,4′-bis[N,N′-3-tolylamino]-3,3′-dimethylbiphenyl (HMTPD).

9. The heterostructure light-emitting device of claim 5 , wherein the hole blocking layer is 4-biphenyloxolato 4,4′-N,N′-dicarbazole-biphenyl (CBP), aluminum(III)bis(2-methyl-8-quinolinato)4-phenylphenolate (BAlq), or bathocuproine (BCP).

10. The heterostructure light-emitting device of claim 6 , wherein the hole blocking layer is 4-biphenyloxolato 4,4′-N,N′-dicarbazole-biphenyl (CBP), aluminum(III)bis(2-methyl-8-quinolinato)4-phenylphenolate (BAlq), or bathocuproine (BCP).

11. The heterostructure light-emitting device of claim 5 , wherein the electron transporting layer is tris(8-quinolinolato)aluminum (Alq3).

12. The heterostructure light-emitting device of claim 6 , wherein the electron transporting layer is tris(8-quinolinolato)aluminum (Alq3).

13. The heterostructure light-emitting device of claim 5 , wherein the host material is naphthylphenylbiphenylamine (NPB), 3-phenyl-4-(1′-naphthyl)-5-phenyl-1,2,4-triazole (TAZ), bathocuproine (BCP), 4,4′-N,N′-dicarbazole-biphenyl (CBP), or 1,3-bis(N,N′-t-butylphenyl)-1,3,4-oxadiazole (OXD7).

14. The heterostructure light-emitting device of claim 6 , wherein the host material is naphthylphenylbiphenylamine (NPB), 3-phenyl-4-(1′-naphthyl)-5-phenyl-1,2,4-triazole (TAZ), bathocuproine (BCP), 4,4′-N,N′-dicarbazole-biphenyl (CBP), or 1,3-bis(N,N′-t-butylphenyl)-1,3,4-oxadiazole (OXD7).

15. The heterostructure light-emitting device of claim 6 , wherein the blue emissive layer comprises 9,10-bis-(β-naphthyl)-anthracene (BNA), naphthylphenylbiphenylamine (NPB), 3-phenyl-4-(1′-naphthyl)-5-phenyl-1,2,4-triazole (TAZ), 4-biphenyloxolato 4,4′-N,N′-dicarbazole-biphenyl (CBP), bathocuproine (BCP), aluminum(III) bis(2-methyl-8-quinolinato)4-phenylphenolate (BAlq), or 1,3-bis(N,N′-t-butylphenyl)-1,3,4-oxadiazole (OXD7).

16. The heterostructure light-emitting device of claim 5 , further comprising a plurality of emissive layers.

17. The heterostructure light-emitting device of claim 6 , further comprising a plurality of emissive layers.

18. The heterostructure light-emitting device of claim 5 , further comprising at least one filter layer.

19. The heterostructure light-emitting device of claim 6 , further comprising at least one filter layer.

20. The heterostructure light-emitting device of claim 6 , wherein the device emits orange light at CIE — 1931 coordinates of (0.37, 0.58).

21. The heterostructure light-emitting device of claim 6 , wherein the device emits white light at CIE — 1931 coordinates from about (0.26, 0.31) to about (0.33, 0.39), with increasing voltage.

22. The heterostructure light-emitting device of claim 6 , wherein the device emits white-light with distinct emission peak maxima at 436, 532 and 570 nm in an electroluminescent spectrum.

23. A flat panel display comprising at least one heterostructure light-emitting device of claim 5 .

24. A flat panel display comprising at least one heterostructure light-emitting device of claim 6 .

25. A method of fabricating a light-emitting device, the method comprising:

depositing a first electrode on a substrate;

depositing a hole transporting layer on the first electrode;

depositing at least one emissive layer on the hole transport layer, the emissive layer comprising at least one host material and/or one emitting/dopant complex, wherein the emitting/dopant complex is the organometallic complex of claim 1 ;

depositing a hole blocking layer on the emissive layer;

depositing an electron transporting layer on the hole blocking layer; and

depositing a second electrode on the electron transporting layer.

26. A method of fabricating a light-emitting device, the method comprising:

depositing a first electrode on a substrate;

depositing a hole transporting layer on the first electrode;

depositing at least one emissive layer on the hole transport layer, the emissive layer comprising at least one host material and/or one emitting/dopant complex, wherein the emitting/dopant complex is the organometallic complex of claim 1 ;

depositing a hole transporting layer on the emissive layer;

depositing a blue emissive layer on the hole transporting layer;

depositing a hole blocking layer on the blue emissive layer;

depositing an electron transporting layer on the hole blocking layer; and

depositing a second electrode on the electron transporting layer.