A structurally unique and strongly luminescent nonporous 3D coordination polymer (CP) [Cu8I8(methyldithiane)(4)](n), CP3, has been prepared in a quasi-anticipated manner from 2-methyl-1,3-dithiane, LI, and Cul. This CP incorporates an unprecedented Cu818 cluster built upon two side-fused open cubanes. The crystal structure of CP3 has been determined at 100, 150, 200, 250, 300, 350, and 400 K to study the temperature dependence of the Cu"""Cu distances. Two other topological 1D and 2D CPs isomers of formula [{Cu2I2(L1)(2)](n) featuring dinuclear {Cu-2(mu(2)-I)2} rhomboids were also obtained independently by control of the reaction conditions. These two CPs convert into CP3 in hot PrCN, thus indicating that this latter material is the thermodynamic product. While CPI and CP2 are not emissive, CP3 exhibits an intense luminescence due to the incorporation of the octanuclear Cu8I8 clusters as secondary building units within the network. The pho rationalized by means of DFT and TDDFT computing. Furthermore, by ATG and DSC analyses. The Raman spectra of CPI-3 have been S tophysical properties of CP3 have been investigated and the thermal stability of these materials has been studied recorded in the solid state in the 50-500 cm(-1) region.