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Under hydro(solvo)thermal conditions, four organic bidentate bridging N,N′-donor ligands 1,3-bis(2-methylimidazol-1-yl)propane (L1), 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L2), 1,2-bis(2-methyl-1H-imidazol-1-ylmethyl)benzene (L3) and 5,6,7,8-tetrahydroquinoxaline (L4) were employed to react with CuBr/CuI, generating four 2-D layered copper(i)–polymer coordination polymer materials [Cu2Br2(L1)] 1, [CuI(L2)] 2, [CuI(L3)] 3 and [CuI(L4)0.5] 4. In 1–4, different Cu–X motifs are found: a cubic Cu4Br4 core in 1; a castellated Cu–I single chain in 2; a rhombic Cu2I2 core in 3; and a staircase-like Cu–I double chain in 4. The 2-D layer networks of 1–3 can all be simplified into a simple 44 topology (planar for 1 and 3; wave-like for 2), while the 2-D layer network of 4 has a 63 topology. The photoluminescence behaviors of 1–4 under a UV lamp suggest that 1 and 2 possess fluorescence thermochromism properties. Under the UV lamp, with the decrease in temperature, (i) 1 exhibits a yellow-to-red emission; (ii) 2 exhibits a yellow-to-green emission; (iii) 3 always emits green light; and (iv) 4 never emits light. These are further confirmed by their emission spectra. From 297 K to 77 K, the emission of 1 exhibits a large red shift from 561 nm to 623 nm; the emission of 2 exhibits a large blue shift from 571 nm to 515 nm; only a minor red shift is observed for the emission of 3; and no peaks appear in the emission spectra of 4. The crystal data of 1 and 2 at different temperatures have been collected for revealing the origination of their fluorescence thermochromism properties. Based on the above investigations, the effect of the rigidity/flexibility of the organic ligand on the fluorescence thermochromism properties of copper(i)–polymer coordination polymer materials is discussed. The quantum yields at 297 K and the photoluminescence lifetimes at 297 K and 77 K for 1–3 were also measured for better understanding their photoluminescence properties. [ABSTRACT FROM AUTHOR]

Based on a strategy of incorporating the SCN − group into the organically templated halocadmate, the reactions of CdCl 2 , SCN − , and bisimidazole molecules in a strong acidic environment at 4 °C were carried out, creating two new organically templated 2-D layered thiocyanato-chlorocadmates [H 2 (L1)][Cd 2 Cl 5 (SCN)] (L1 = bis(1H-imidazole-1-yl)methane) 1 and [H 2 L2] 2 [Cd 5 Cl 12 (SCN) 2 ] (L2 = 1,3-bis(2-ethylimidazol-1-yl)propane) 2 . Both layers are based on a kind of tetranuclear Cd–Cl cluster. Since the employed organic cations are different, the neighboring tetranuclear Cd–Cl clusters are linked together by the different bridges into the 1-D endless chains. In 1 , the Cl − ions act as the bridges, while in 2 , the CdCl 6 units serve as the bridges. Finally, the 1-D Cd–Cl chains are further linked by SCN − into the 2-D layer networks of 1 and 2 . Both layers possess a simple (4,4) topology. Based on the structural characterization of the title compounds, the role of the introduced SCN − group on the organically templated halocadmates is discussed. [ABSTRACT FROM AUTHOR]