Hydrothermal Syntheses, Crystal Structures and Photoluminescent Properties of Three Metal‐Cluster Based Coordination Polymers Containing Mixed Organic Ligands

Three novel metal‐cluster based coordination polymers (MCCPs) with formulae [Zn 4 (μ 3 ‐OH) 2 (H 2 O) 2 (sip) 2 (4,4′‐bpy) 2 ]·3H 2 O (MCCP‐4), [Cd 4 (μ 3 ‐OH) 2 (H 2 O) 2 (sip) 2 (4,4′‐bpy) 4 ]·H 2 O (MCCP‐5) and [Cd 6 (μ 3 ‐OH) 4 (μ 2 ‐OH 2 ) 2 (OH 2 ) 2 (nip) 4 (4,4′‐bpy) 3 ]·3H 2 O (MCCP‐6) [H 2 sip = 5‐sulfoisophthalic acid, H 2 nip = 5‐nitroisophthalic acid and 4,4′‐bpy = 4,4′‐bipyridyl] were hydrothermally synthesized and characterized by single‐crystal X‐ray diffraction studies. MCCP‐4 crystallizes in the triclinic space group P $\bar 1$ with a = 10.106(2), b = 10.851(2), c = 11.125(2) Å, α = 105.66(3), β = 112.63(3), γ = 98.18(3)°, V = 1041.8(4) Å 3 , and Z = 2. MCCP‐5 crystallizes in the monoclinic space group C 2/ c with a = 25.602(1), b = 16.571(1), c = 13.322(1) Å, β = 92.524(1)°, V = 5646.4(2) Å 3 , and Z = 4. MCCP‐4 and ‐5 consist of similar [M 4 (μ 3 ‐OH) 2 ] 6+ tetranuclear building units that are joined through sip and 4,4′‐bpy ligands to generate a two‐dimensional structure (MCCP‐4) and a three‐dimensional structure (MCCP‐5), respectively. MCCP‐6 crystallizes in the triclinic space group P $\bar 1$ with a = 14.295(2), b = 14.472(2), c = 20.204(3) Å, α = 73.362(3), β = 82.200(3), γ = 62.769(2)°, V = 3560.9(10) Å 3 , and Z = 2. MCCP‐6 contains unprecedented [Cd 6 (μ 3 ‐OH) 4 (μ 2 ‐OH 2 ) 2 ] 8+ hexanuclear building units which are linked through nip and 4,4′‐bpy ligands to afford a two‐dimensional structure. The infrared spectroscopy, thermal stability and photoluminescence of the three complexes were studied. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)