NOVELTY - Aryl group substituted metal complexes (I) are new.    USE - (I) are useful as emitting compound in the electronic device, preferably organic electroluminescent device, organic integrated circuit, organic field-effect transistor, organic thin-film transistor, organic light-emitting transistor, organic solar cell, organic optical detector, organic photoreceptor, organic field-quench device, light-emitting electrochemical cell or organic laser diode (claimed).    ADVANTAGE - (I) can be prepared in high yield and provides organic electroluminescent device with high thermal stability, good efficiency, high service life and operating voltage.    DETAILED DESCRIPTION - Aryl group substituted metal complexes of formula (I) are new.    M = transition metal, preferably Pt(II), Pd(II), Ni(II), Rh(I), Ir(I) or Au(II);    A = N, P (both preferred), B, C- or CR;    Y1 = C(R)2, NR, O, S or a single bond (preferred);    Z = C or N, provided that both Zs are C, when Ar3 is a six-membered (hetero)aryl ring, and either both Zs are C or one of the Z is C, and the other Z is N, when Ar3 is five-membered heteroaryl ring;    D1 = C or N;    Ar1D1, Ar13C, Ar2D1, Ar23C = 5-13 membered (hetero)aryl ring optionally substituted by one or more R1;    Ar3Z, Ar3+3C = 5-10 membered (hetero)aryl ring optionally substituted by one or more R1; either    R, R1 = linear 1-20C-alkyl, linear 1-20C-alkoxy, linear 1-20C-thioalkoxy, 2-20C-alkenyl, 2-20C-alkynyl, branched or cyclic 3-20C-alkyl, branched or cyclic 3-20C-alkoxy, branched or cyclic 3-20C-thioalkoxy (where one or more nonadjacent CH2 groups are optionally replaced by R2C=CR2, CC, Si(R2)2, C=O, NR2, O, S or CONR2 and one or more H-atoms are optionally replaced by D, F, Cl, Br, I or CN), 5-60 membered (hetero)aryl ring, 5-40 membered (hetero)aryloxy ring, 5-40 membered (hetero)aralkyl ring, 10-40 membered di(hetero)arylamino ring or 10-40 membered arylheteroarylamino ring (all optionally substituted by R2), H, D, F, Cl, Br, I, N(R2)2, CN, NO2, OH, COOH, C(=O)N(R2)2, Si(R2)3, B(OR2)2, C(=O)R2, P(=O)(R2)2, S(=O)R2, S(=O)2R2 or OSO2R2; or    2R, 2R1 = a mono-or polycyclic, aliphatic or aryl ring system;    R1Ar1, R1Ar2 = a monocyclic, polycyclic, aliphatic or aryl ring system;    R2 = linear 1-20C-alkyl, linear 1-20C-alkoxy, linear 1-20C-thioalkoxy, 2-20C-alkenyl, 2-20C-alkynyl, branched or cyclic 3-20C-alkyl, 3-20C-alkoxy, 3-20C-thioalkoxy (where one or more nonadjacent CH2 groups are replaced by R3C=CR3, CC, Si(R3)2, C=O, NR3, O, S or CONR3 and one or more H atoms are replaced by D, F, Cl, Br, I, CN or NO2), 5-60 membered (hetero)aryl ring, 5-40 membered (hetero)aryloxy ring, 5-40 membered (hetero)aralkyl ring, 10-40 membered diarylamino ring, 10-40 membered diheteroarylamino ring, 10-40 membered arylheteroarylamino ring (all optionally substituted by R3, where two or more of adjacent R3 together forms a mono- or polycyclic, aliphatic ring), H, D, F, Cl, Br, I, N(R3)2, CN, NO2, Si(R3)3, B (OR3)2, C(=O)R3, P(=O)(R3)2, S(=O)R3, S(=O)2R3 or OSO2R3; and    R3 = H, D, F, 1-20C-aliphatic, (hetero)aryl ring (in which one or more H atoms are optionally replaced by F), where two or more of R3 optionally combine to form a mono-or polycyclic, aliphatic ring.    INDEPENDENT CLAIMS are included for:    (1) the preparation of (I);    (2) a formulation, preferably a solution, a suspension or a miniemulsion comprising (I) and at least one solvent, or a mixture containing (I) and at least one further compound; and    (3) an electronic device, preferably organic electroluminescent device, organic integrated circuit, organic field-effect transistor, organic thin-film transistor, organic light-emitting transistor, organic solar cell, organic optical detector, organic photoreceptor, organic field-quench device, light-emitting electrochemical cell or organic laser diode comprising (I).