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Reaction of CuI with bis(phenylthio)propane in a 1:1 ratio yields the two-dimensional coordination polymer [{Cu(μ(2)-I)(2)Cu}{μ-PhS(CH(2))(3)SPh}(2)](n) (1). The 2D-sheet structure of 1 is built up by dimeric Cu(2)I(2) units, which are connected via four bridging 1,3-bis(phenylthio)propane ligands. In contrast, treatment of 2 equiv of CuI with 1,3-bis(phenylthio)propane in MeCN solution affords in a self-assembly reaction the strongly luminescent metal-organic 2D-coordination polymer [Cu(4)I(4){μ-PhS(CH(2))(3)Ph}(2)](n) (2), in which cubane-like Cu(4)(μ(3)-I)(4) cluster units are linked by the dithioether ligands. The crystallographically characterized one-dimensional (1D) compound [{Cu(μ(2)-Br)(2)Cu}{μ-PhS(CH(2))(3)SPh}(2)](n) (3) is obtained using CuBr. The outcome of the reaction of PhS(CH(2))(5)SPh with CuI also depends of the metal-to-ligand ratio employed. Mixing CuI and the dithioether in a 2:1 ratio results in formation of [Cu(4)I(4){μ-PhS(CH(2))(5)Ph}(2)](n) (4) in which cubane-like Cu(4)(μ(3)-I)(4) clusters are linked by the bridging dithioether ligand giving rise to a 1D necklace structure. A ribbon-like 1D-polymer with composition [{Cu(μ(2)-I)(2)Cu}{μ-PhS(CH(2))(5)SPh}(2)](n) (5), incorporating rhomboid Cu(2)I(2) units, is produced upon treatment of CuI with 1,5-bis(phenylthio)pentane in a 1:1 ratio. Reaction of CuBr with PhS(CH(2))(5)SPh produces the isomorphous 1D-compound [{Cu(μ(2)-Br)(2)Cu}{μ-PhS(CH(2))(5)SPh}(2)](n) (6). Strongly luminescent [Cu(4)I(4){μ-p-TolS(CH(2))(5)STol-p}(2)](n) (7) is obtained after mixing 1,5-bis(p-tolylthio)pentane with CuI in a 1:2 ratio, and the 2D-polymer [{Cu(μ(2)-I)(2)Cu}(2){μ-p-TolS(CH(2))(5)STol-p}(2)](n) (8) results from reaction in a 1:1 metal-to-ligand ratio. Under the same reaction conditions, 1D-polymeric [{Cu(μ(2)-Br)(2)Cu}{μ-p-TolS(CH(2))(5)STol-p}(2)](n) (9) is formed using CuBr. This study reveals that the structure of the self-assembly process between CuX and ArS(CH(2))(m)SAr ligands is hard to predict. The solid-state luminescence spectra at 298 and 77 K of 2 and 4 exhibit very strong emissions around 535 and 560 nm, respectively, whereas those for 1 and 5 display weaker ones at about 450 nm. The emission lifetimes are longer for the longer wavelength emissions (>1.0 μs arising from the cubane species) and shorter for the shorter wavelength ones (<1.4 μs arising from the rhomboid units). The Br-containing species are found to be weakly fluorescent.

Bis(phenylthio)methane (L1) reacts with CuI to yield the 1D-coordination polymer [{Cu 4 (μ 3 -I) 4 }(μ-L1) 2 ] n (1) bearing cubane Cu 4 I 4 clusters as connecting nodes. The crystal structures at 115, 155, 195, and 235 K provided evidence for a phase transition changing from the monoclinic space group C2/c to P2 1 /c. The self-assembly process of CuI with bis(p-tolylthio)methane (L2), bis(4-methoxyphenylthio)methane (L3), and bis(4-bromophenylthio)methane (L4) affords the 1D-coordination polymers [{Cu 4 (μ 3 -I) 4 }(μ-Lx) 2 ] n (x = 2, 3, or 4). Compounds 2 and 4 are isostructural with C2/c low temperature polymorph of 1, whereas the inversion centers and 2-fold axes are lost in 3 (space group Cc). The use of bis(m-tolylthio)methane (L5) has no impact on the composition and overall topology of the resulting 1D ribbon of [{Cu 4 (μ 3 -I) 4 }(μ-L5) 2 ] n (5). Even the coordination of the sterically crowded dithioether bis(5-tert-butyl-2-methylphenylthio)methane (L8) does not alter the network topology generating the 1D polymer [{Cu 4 (μ 3 -I) 4 }(μ-L8) 2 ] n (8). The 1D polymer [{Cu(μ 2 -Br) 2 Cu}(L1) 2 ] (9) results from the coordination of L1 with CuBr in a 1:1 metal-to-ligand ratio. In contrast to the mean Cu•••Cu distances, which are <2.8 Å noted for the Cu 4 (μ 3 -I) 4 clusters in the 1D polymers 1−8, the Cu•••Cu contact within the Cu(μ 2 -Br) 2 Cu rhomboids of 9 [2.9194(8) Å] is above the sum of the van der Waals radii of two Cu atoms. The structural arrangement of 1D polymer [{Cu(μ 2 -Br) 2 Cu}(L3) 2 ] n (11) is quite similar to that of 9. While the reaction of CuBr with L5 results in a similar 1D polymer [{Cu(μ 2 -Br) 2 Cu}(L5) 2 ] n (12), the reaction of CuBr with L2 leads to the dinuclear complex [{Cu(μ 2 -Br) 2 Cu}(η 1 -L2) 4 ] (10) ligated by four pendent bis(p-tolylthio)methane ligands. The ligation of bis(o-tolylthio)methane, L6, on CuBr also yields a discrete complex [{Cu(μ 2 -Br) 2 Cu}(MeCN) 2 (η 1 -L6) 2 ] (13) bearing MeCN and dangling dithioether ligands. A strong luminescence is detected for all CuI polymers, all exhibiting emission lifetimes in the microsecond time scale (i.e., phosphorescence). The polymers containing the Cu 4 I 4 core (1−8) exhibit the typically observed low-energy band and sometimes a weaker high-energy band. The nature of the low-energy band was proposed based on literature DFT and TDDFT computations and is predicted to be a mixture of cluster-centered (CC*) and metal/halide-to-ligand charger transfer (M/XLCT). An approximate relationship between the Cu•••Cu distance and the emission maxima corroborates the CC* contribution to the nature of the excited states. The emission of the rhomboid-containing materials is assigned to M/XLCT based on literature works on similar motifs.