TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Component: The electroluminescent layer further comprises one or more of 6 host compound(s), e.g. compound(s) of formula (Ar'11)a-X-(Ar'12)b (2) or (Ar'13)c-Y'-(Ar'14)d (3). The organic layer comprises compound(s) from arylamine compounds or styrylamine compounds. It further comprises metal(s) including organic metals of Group 1, Group 2, 4th period and 5th period transition metals, lanthanide metals or d-transition elements.X=6-60C arylene or 4-60C heteroarylene;Y'=anthracenylene;Ar'11-Ar'14=H, (1-60C) alkyl, (1-60C)alkoxy, halo, (4-60C)heteroaryl, (5-60C)cycloalkyl or (6-60C)aryl, where the alkyl, cycloalkyl, aryl or heteroaryl may be further substituted by substituent (s) from (6-60C)aryl or (4-60C)heteroaryl with or without substituent (s) from deuterium, (1-60C)alkyl with or without halo substituent, (1-60C) alkoxy, (3-60C)cycloalkyl, halo, CN, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl or tri(6-60C)arylsilyl, (1-60C)alkyl with or without halo substituent, (1-60C)alkoxy, (3-60C)cycloalkyl, halo, CN, tri(1-60C)alkylsilyl, di(1-60C)alkyl(6-60C)arylsilyl or tri(6-60C)arylsilyl; anda-d=1-4. EXAMPLE - A transparent electrode indium tin oxide (ITO) thin film 2 prepared from a glass substrate for an organic LED (OLED) 1 was subjected to ultrasonic washing sequentially using trichloroethylene, acetone, ethanol and distilled water, and stored in isopropanol for later use. The ITO substrate was mounted on a substrate holder of a vacuum deposition apparatus. After filling 4,4', 4'-tris(N,N-(2-naphthyl)-phenylamino)triphenylamine in a cell of the vacuum deposition apparatus, the pressure inside the chamber was reduced to 10-6 torr. Then, 4, 4', 4"-tris(N,N-(2-naphthyl)-phenylamino)triphenylamine was evaporated by applying electrical current to the cell. A hole injecting layer 3 having a thickness of 60 nm was formed on the ITO substrate. Subsequently, after filling N,N'-bis( alpha -naphthyl)-N,N'-diphenyl-4,4'-diamine (NPB) in another cell of the vacuum deposition apparatus, NPB was evaporated by applying electrical current. A hole transport layer 4 having a thickness of 20 nm was formed on the hole injecting layer. After forming the hole injecting layer and the hole transport layer, an electroluminescent layer 5 was formed. Compound of formula (H-33) was filled in a cell of a vacuum deposition apparatus as a host, and compound of formula (223) (having cis content of greater than or equal to 80 wt.% but less than 100 wt.%, and trans content of greater than 0 wt.% but less than or equal to 20 wt.%) was filled in another cell as a dopant. The two materials were evaporated at different speed, so that an electroluminescent layer 5 having a thickness of 30 nm was formed on the hole transport layer at 2-5 wt.%. Tris(8-hydroxyquinoline)-aluminum(III) was deposited with a thickness of 20 nm as an electron transport layer 6. Then, lithium quinolate was deposited with a thickness of 1-2 nm as an electron injection layer 7. Then, an aluminum cathode 8 having a thickness of 150 nm was formed using another vacuum deposition apparatus to manufacture an OLED. Each OLED electroluminescent material was purified by vacuum sublimation at 10-6 torr.