NOVELTY - Copper(I)complexes are new.    USE - (A) are useful as emitter or absorber in an optoelectronic component, which is organic LED, light-emitting electrochemical cells, organic-LED sensors, preferably non-hermetically externally shielded gas and vapor sensors, organic solar cells, organic field-effect transistors, organic lasers, down-conversion elements, organic diode and organic transistors (all claimed).    ADVANTAGE - (A) are nontoxic. (A) provide optoelectronic devices with a wide range of achievable emission colors and high emission quantum yield, preferably greater than 50% without quenching effects.    DETAILED DESCRIPTION - Copper(I)complexes of formula (A) are new.    X = Cl, Br, I, CN and/or SCN;    NarcE = a bidentate ligand (B1), nitrogen containing aryl group of formula (B1a)-(B1d), where the substituent is linear, branched or cyclic long-chain 1-30C-alkyl, linear, branched or cyclic long-chain 1-30C-alkoxy, linear or branched long-chain or cyclic 1-30C-perfluoroalkyl or short-chain polyethers with a chain length of 3-50 repeating units, where NarcE is an optionally substituent, which increases the solubility of (I) in an organic solvent;    E = phosphanyl/arsenyl containing group of formula R2E;    R = alkyl, aryl, alkoxy, phenoxy or amide;    N = imine function which is a component of 5-membered N-heteroaryl ring consisting of triazole, oxadiazole, thiadiazole, tetrazole, oxatriazole or thiatriazole;    arc = at least one carbon atom that is likewise a component of the aryl group, where C atom being directly adjacent to both the imine nitrogen atom and to P or Ar atom;    Y1 = NR2, O or S; and either    R1-R3 = H, halo, a substituent bonded over O, N or Si, linear, branched or cyclic alkyl, aryl, heteroaryl, alkenyl and/or alkynyl, or substituted branched or cyclic alkyl, aryl, heteroaryl and/or alkenyl groups substituted with halo or D, or branched or cyclic alkyl or further donor or acceptor groups e.g. amines, carboxylates or their esters or CF3; or    R2R3 = optionally forms a fused ring system.    Where: NarcE optionally comprises at least one substituent (Q) for increasing the solubility of (A) in an organic solvent, and (Q) is linear, branched or cyclic 1-30C-alkyl, 1-30C-alkoxy, 1-30C-perfluoroalkyl and short chain polyether with 3-50 repeating units. INDEPENDENT CLAIMS are included for:    (1) the preparation of (I);    (2) an optoelectronic component comprising (A);    (3) the preparation of the optoelectronic component using (A);    (4) the bidentate ligand (B1); and    (5) the preparation of the bidentate ligand (B1) comprising reacting a nitrogen containing aryl compound of formula (B1aa)-(B1dd) with a chlorinated compound of formula (E(R1)2Cl) in the presence of a base to obtain (B1a)-(B1d), respectively.