Copper complex comprising a structure of formula A with X* = independently selected from the group consisting of Cl, Br, I, CN, OCN, SCN, alkynyl and N 3, N*∩E = a divalent ligand with E = phosphanyl/arsenyl/antimonyl radical of the R 2 E form (with R = alkyl, aryl, heteroaryl, alkoxy, phenoxy or amide); N* = imine function which is part of an aromatic group preferably selected from pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, triazinyl, tetrazinyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,4-oxadiazolyl, 1,2,4-thiadiazolyl, tetrazolyl, 1,2,3,4-oxatriazolyl, 1,2,3,4-thiatriazolyl, quinolyl, isoquinolyl, quinoxalyl, quinazolyl, which may each optionally have further substitution and/or be fused; "n" = at least one carbon atom which is likewise part of the aromatic group, wherein the at least one carbon atom is either directly adjacent to the imine nitrogen atom or to the phosphorus, arsenic or antimony atom; R 2 D-B-DR 2 = a bidentate ligand with D = independently selected from the group consisting of P, As and Sb, wherein D is bonded via a bridge B to a further D radical which is the same as or different from D, wherein the bridge B is one or more identical or different, substituted or unsubstituted alkylene, alkenylene, alkynylene or arylene groups or -O-, -NR- or -SiR 2 -, or a combination thereof, wherein the R radicals are each independently selected from the group consisting of hydrogen, deuterium, halogen and substituents bonded directly or via oxygen atoms (-OR), nitrogen atoms (-NR 2), silicon atoms (-SiR 3) or sulphur atoms (-SR), and alkyl (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl, alkenyl, alkynyl groups or substituted alkyl (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl and alkenyl groups (with substituents such as halogens or deuterium, alkyl groups (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl groups), and further commonly known donor and acceptor groups, for example amines, carboxylates and esters thereof, and CF 3 groups; wherein two or more adjacent R radicals may optionally lead to fused ring systems; wherein N*∩E and/or R 2 D-B-DR 2 optionally has at least one substituent for improving charge carrier transport and/or for increasing the solubility of the copper complex in an organic solvent. X* = independently selected from the group consisting of Cl, Br, I, CN, OCN, SCN, alkynyl and N 3, N*∩E = a divalent ligand with E = phosphanyl/arsenyl/antimonyl radical of the R 2 E form (with R = alkyl, aryl, heteroaryl, alkoxy, phenoxy or amide); N* = imine function which is part of an aromatic group preferably selected from pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, triazinyl, tetrazinyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,4-oxadiazolyl, 1,2,4-thiadiazolyl, tetrazolyl, 1,2,3,4-oxatriazolyl, 1,2,3,4-thiatriazolyl, quinolyl, isoquinolyl, quinoxalyl, quinazolyl, which may each optionally have further substitution and/or be fused; "n" = at least one carbon atom which is likewise part of the aromatic group, wherein the at least one carbon atom is either directly adjacent to the imine nitrogen atom or to the phosphorus, arsenic or antimony atom; E = phosphanyl/arsenyl/antimonyl radical of the R 2 E form (with R = alkyl, aryl, heteroaryl, alkoxy, phenoxy or amide); N* = imine function which is part of an aromatic group preferably selected from pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, triazinyl, tetrazinyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,4-oxadiazolyl, 1,2,4-thiadiazolyl, tetrazolyl, 1,2,3,4-oxatriazolyl, 1,2,3,4-thiatriazolyl, quinolyl, isoquinolyl, quinoxalyl, quinazolyl, which may each optionally have further substitution and/or be fused; "n" = at least one carbon atom which is likewise part of the aromatic group, wherein the at least one carbon atom is either directly adjacent to the imine nitrogen atom or to the phosphorus, arsenic or antimony atom; R 2 D-B-DR 2 = a bidentate ligand with D = independently selected from the group consisting of P, As and Sb, wherein D is bonded via a bridge B to a further D radical which is the same as or different from D, wherein the bridge B is one or more identical or different, substituted or unsubstituted alkylene, alkenylene, alkynylene or arylene groups or -O-, -NR- or -SiR 2 -, or a combination thereof, wherein the R radicals are each independently selected from the group consisting of hydrogen, deuterium, halogen and substituents bonded directly or via oxygen atoms (-OR), nitrogen atoms (-NR 2), silicon atoms (-SiR 3) or sulphur atoms (-SR), and alkyl (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl, alkenyl, alkynyl groups or substituted alkyl (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl and alkenyl groups (with substituents such as halogens or deuterium, alkyl groups (unbranched, branched or cyclic), heteroalkyl, aryl, heteroaryl groups), and further commonly known donor and acceptor groups, for example amines, carboxylates and esters thereof, and CF 3 groups; wherein two or more adjacent R radicals may optionally lead to fused ring systems; wherein N*∩E and/or R 2 D-B-DR 2 optionally has at least one substituent for improving charge carrier transport and/or for increasing the solubility of the copper complex in an organic solvent.