TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation: No preparation method is given. Preferred Components: The copper(I) complex exhibits: a singlet-triplet splitting delta E(S1-T1) value of less than 1500 cm-1, preferably less than 500 cm-1; an emission quantum yield of greater than 40%, preferably greater than 70%; an emission lifetime of not greater than 10 mu s, preferably less than 3 mu s; and a solubility in organic solvents of at least 10 g/liter.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Method: The production of optoelectronic device, comprises wet-chemical method comprising: (a) applying a first emitter complex dissolved in a first solvent on a carrier; and (b) applying a second emitter complex dissolved in a second solvent on the carrier, where the first emitter complex and/or the second emitter complex is copper(I) complex (I). The first emitter complex is insoluble in the second solvent and the second emitter complex is insoluble in the first solvent. The method further comprises applying a third emitter complex dissolved in the first solvent or in a third solvent, on the carrier, where the third emitter complex is the copper(I) complex (I). Preferred Components: The optoelectronic device is a white light organic light-emitting diode (OLED). The first emitter complex is a red light emitter. The second emitter complex is a green light emitter. The third emitter complex is a blue light emitter. The optoelectronic device, preferably OLED, comprises an emitter layer comprising (I) (2-100 wt.%, preferably 4-30 wt.%, based on the total weight of the emitter layer). Preferred Definitions:    A-A = substituted 2,2'-bipyridine derivative (substituted in 3,3'-position by (CH3-(CH2)n-) (optionally branched) or aryl, preferably phenyl, or 1,10-phenanthroline derivative (substituted in 2,9-position with (CH3-(CH2)n-) (optionally branched) or aryl, preferably phenyl;    n = 1-20; and    R = (-(CH2)n-CH3) (optionally branched), 6-20C aryl, preferably phenoxy (both substituted by halo, alkoxy or silane group), (-O-(CH2)n-CH3), aryloxy, preferably phenoxy or silane group, preferably (-Si(CH3)3), where the alkyl- and aryl groups are fused to form fused ring systems, and R increases the solubility of copper(I) complex in organic solvents and/or increases the hole or electron conductivity.    SPECIFIC COMPOUNDS - 9 Compounds (I) are disclosed e.g. copper complexes of formula (Ia)-(Ie).    EXAMPLE - Tetrabutylammonium-bis((diphenylphosphino)methyl)diphenylborate and tetrakis(acetonitrile-N)copper(I) hexafluorophosphate(V) were stirred in acetonitrile under nitrogen atmosphere. After 2 hours 4,7-dihexyl-2,9-dimethyl-(1,10)phenanthroline was added to the reaction mixture. Then the reaction mixture was worked up to obtain (Ia).