TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I) comprises reacting a free ligand with metal alcoholate of formula (M(OR)n) (V), metalketoketonate compound of formula (VI), metal halide compound of formula (M(Hal)n) (VII) and dimeric metal complex of formula (VIII) or metal compounds containing alkoxide, halide, hydroxy and/or ketoketonate group.Hal = F, Cl, Br or I. Preferred Definitions:    A = O or S;    V1 = 1-80 atoms from (III)-(VI) main group or 3-6-membered homo or heterocycle, which combines partially with L or L with L1 via a covalent bond;    M = Ir, Pt, Cr, Mo, W, Re, Ru, Os, Rh, Ni, Pd, Cu, Ag or Au; and    L1 = CO, nitric oxide, alkyl cyanides, aryl cyanides, alkyl isocyanides, aryl isocyanides, amines, phosphines, phosphites, arsines, stibines, nitrogen-containing heterocycles, carbenes, hydride, deuteride, F-, Cl-, Br-, I-, alkyl acetylide ion, aryl acetylide ion, cyanide, cyanate, isocyanate, thiocyanate, isothiocyanate, alcoholates, aliphatic or aromatic (thio)alcoholates, amides, carboxylates, aryl, O2-, S2-, carbides, nitrenes, diamines, imines, diimines, diphosphines, 1,3-diketonates derived from 1,3-diketones, 3-ketonate derived from 3-keto esters, carboxylates derived from amino carboxylic acids, salicyliminate derived salicylimines, dialcoholate, dithiolates, borates, nitrogen heterocycles and ligands, which are formed by a combination of 23 (hetero)aryl groups e.g. of formulae (IX)-(XIII).    EXAMPLE - A mixture of 10 mmoles of sodium bisacetylacetonato-dichloro-iridate(III) and 22 mmoles of iridium complex of formula (A1) was slowly heated with stirring at 20 degrees C for 20 minutes under inert gas (nitrogen or argon). Further acetylacetone was added for 20 hours. After cooling under a protective gas, the sintered cake was comminuted mechanically. Then, 100 g of glass beads with a diameter of 3 mm in 100 ml of ethyl acetate was added. The obtained fine suspension was decanted, dried in vacuum and purified to obtain iridium complex of formula (Ia).