New ternary SeRuCu octahedral-based complexes, namely, CuX-capped SeRu5 clusters [SeRu5(CO)14(μ3-CuX)]2− (2a–2c; X = Cl, Br, I), bis-CuX-capped SeRu5 clusters [SeRu5(CO)14(μ3-CuX)2]2− (3a, 3b; X = Cl, Br), Cu4X2-bridged di-SeRu5 clusters [{SeRu5(CO)14}2(μ6-Cu4X2)]2− (4a, 4b; X = Cl, Br), and bis-CuX-incorporated Se2Ru4 clusters [Se2Ru4(CO)10(μ-CuX)2]2− (5a–5c; X = Cl, Br, I), were prepared from the reaction of the binary cluster [SeRu5(CO)14]2− (1) with CuX under appropriate conditions. Their solid-state packing formed cluster-based 1D-supramolecular chains, which were stabilized by CH⋯X/Y (X = halides; Y = O) H-bonding between CuX/COs of cluster anions and the CH moieties of the [PPh4]+ or [PPN]+ cations. In addition, electrochemical studies showed that the successive anodic shifts were found for 1–4b, tuned by the incoming CuBr fragments introduced into the parent SeRu5 cluster, supported by their decreasing HOMO levels and increasing ionization energies. Solid-state diffuse reflectance spectra showed these SeRuCu complexes exhibited semiconducting behaviors with the low and tunable energy gaps of 0.82–1.08 eV. Significantly, the solid-state absorptions of 2b and 4b were red-shifted compared with the corresponding Te analogues, which was explained by the larger numbers of the density of states (DOS) close to the HOMO for the selenide cases.