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Reactions of the [(tppm)Au3Cl3] [tppm = tris(diphenylphosphanyl)methane] precursor and CuI ions with a stoichiometric amount of the corresponding linear mono- [HC2(C6H4) nC6H5; n = 1, 2] and diacetylenes [HC2(C6H4) nC2H; n = 1-3] that contain extended polyaryl moieties afford a series of luminescent heterometallic complexes with a common structural motif based on the {(AuC2)3Cu} cluster core. The complexes obtained were characterized by using X-ray crystallography and NMR spectroscopy. All compounds studied display dual singlet and triplet luminescence, the former component of which can be completely suppressed in concentrated solution by a self-absorption phenomenon. The results of the photophysical measurements together with the quantum chemical calculations (PBE0-DFT level of theory) indicate that singlet emission originates mainly from copper-perturbed intraligand transitions, whereas the phosphorescence can be assigned to the {(AuC2)3Cu} core-centered transitions. Due to the low contribution of the gold atoms to the orbitals responsible for the singlet and triplet emission, the emissive excited states are very weakly coupled, thereby resulting in a negligible energy transfer between these excited states. [ABSTRACT FROM AUTHOR]