NOVELTY - Metal(I) complex (A) is new.    USE - (A) is useful as an emitter or absorber in an optoelectronic component, including organic light-emitting devices (OLEDs), light-emitting electrochemical cells, OLED-sensors, preferably in non-hermetically sealed to the outside gas and steam sensors, organic solar cells, organic FET, organic lasers and down-conversion elements, for the conversion of UV-radiation or blue light into visible light, preferably green, yellow or red light (down-conversion) (all claimed).    ADVANTAGE - (A) improves color, brightness, thermal stability, service life and luminous efficiency of the optoelectronic component.    DETAILED DESCRIPTION - Metal(I) complex of formula (A) is new.    M = Cu or Ag;    X = Cl, Br, I, CN, OCN, SCN, alkynyl, or N3;    E-bond-D1 = bidentate ligand;    E = RR1aE1, provided that when E1 is N, P, As, or Sb and when RE1 is E1 = C1, O, or S;    E1 = N, where N is not an imine nitrogen atom or part of an N heteroaromatic ring, P, C1, O, S, As, or Sb;    C1 = divalent carbene carbon atom;    R, R1a = H, halo, and substituents, which are bound directly or via oxygen (-OR), nitrogen (-NR2), silicon (-S1R3) or sulfur atoms (-SR), alkyl, heteroalkyl, aryl, heteroaryl, alkenyl (all optionally substituted with substituents such as halo, D, alkyl, heteroalkyl, aryl, or heteroaryl), alkynyl, additional donor or acceptor groups or CF3 groups;    D1 = RR1aD2, provided that when D2 is N, P, As, or Sb, or RD1, provided that when D2 is C1, O, or S;    D2 = N, where N is not an imine nitrogen atom or part of an N heteroaromatic ring, P, C1, O, S, As, or Sb;    bond = three-part unit consisting of Q, Y1 and Z, which are bound to each other; and    Q, Y1 and Z = NR, O, S, PR, alkyl, heteroalkyl, aryl, heteroaryl, alkenyl (all optionally substituted with substituents such as halo, D, alkyl, heteroalkyl, aryl, or heteroaryl), alkynyl, additional donor or acceptor groups, preferably amines, carboxylates, and their esters, or CF3, which are optionally further substituted and/or fused, where optional Ek1D1 comprises at least one substituent to improve the charge carrier transport and/or to increase the solubility of the metal(I) complexes in an organic solvent.    INDEPENDENT CLAIMS are included for:    (1) the preparation of (A);    (2) use of (A) as an emitter or absorber in an optoelectronic component;    (3) producing the optoelectronic component; and    (4) modifying the emission- and/or absorption characteristics of the electronic component, comprising incorporating (A) in a matrix material for the conduction of electrons or holes in the optoelectronic component.