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Six Zn/Cd metal–organic frameworks (MOFs), {[Zn2(dppa)(bpy)2(H2O)]·H2O}n (1), {[Zn2(dppa)(phen)2(H2O)]·3H2O}n (2), [Cd(H2dppa)(bpy)]n (3), {[Cd2(dppa)(dye)]·H2O}n (4), {[Cd4(dppa)2(H2O)9]·H2O}n (5) and {[Cd2(dppa)(bpe)2(H2O)]·H2O}n (6) (H4dppa = 5-(3′4′-dicarboxylphenoxy)isophthalic acid, phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine, dye = 2,2′-dipyridylamine, bpe = 1,2-bis(4-pyridy) ethane), were synthesized and structurally characterized by elemental analyses, plasma (ICP) spectrometry, IR spectroscopy, and single-crystal X-ray diffraction analyses. 1–3 are 1D ring chains. 4 shows a 2D bilayer network based on a tetranuclear cadmium cluster linked by (dppa)4− ligands. 5 displays a 2D bilayer network based on a trinuclear cadmium cluster, in which (dppa)4− ion shows two different coordination modes. In contrast to the above MOFs, 6 possesses a 3D network structure based on dinuclear cadmium units cross-linked by (dppa)4− and bpe ligands. For 1–6, weak hydrogen bonding and π⋯π stacking contacts link the discrete 1D chains or 2D networks to form high-dimensional supramolecular structures. Especially, in 1–6, (dppa)4− ligand displays seven different coordination modes and conformations, which may show natural synergy in the structural diversity of the resulting MOFs. The remarkable characteristic of these frameworks is that 2 demonstrates highly selective and sensitive bifunctional luminescent sensing towards acetone and Fe3+ ion. In addition, the thermal stabilities and luminescence properties of the MOFs were studied. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers, [M1.5(stp)(bpe)(H2O)] (M=Mn(1), Cd(2), Zn(3)) have been prepared by hydro-/solvo-thermal reactions of 2-sulfoterephthalate (stp) and 1,2-bis(4-pyridyl)ethane (bpe) ligands with d-block Mn(II), Cd(II) and Zn(II) salts. Complexes 1 and 2 are isomorphic except for the difference of the metal ions, while complexes 1–3 are polymorphic because of the different coordination modes that stp ligand adopts. The left- and right-handed helixes construct 2D layer from metal ions and stp ligands for 1–3, and the anti-bpe ligands as the pillars complete 3D structure. All the three complexes exhibit a new (2,3,4)-connected network with the Schläfli symbol {8;122}4{82; 12; 142; 16}{8}2 based on the different structural motifs. The magnetic properties of 1 reveal that there exists weak antiferromagnetic coupling between the Mn(II) ions. And the solid-state photoluminescence of 2 and 3 can be attributed to the intraligand π–π* transition. [Copyright &y& Elsevier]

abstract Two novel coordination polymers (CPs), [Cd 2 (cbta)(phen) 2 (H 2 O)] n (1), {[Zn 2 (cbta)(phen) 2 ] [Zn 2 (cbta) (phen) 2 (H 2 O)]·4H 2 O} n (2) (H 4 cbta = 1-(2-carboxylphenoxy)-2,3,5-benzene tricarboxylic acid; phen = 1,10-phenanthroline), were synthesized and characterized by elemental analyses, FT-IR spectra, single-crystal X-ray diffraction analyses. CP 1 shows a 2D network structure based on tetranuclear CdII clusters and (cbta)4- ligands, which are arranged in a [ABAB···] alternation to form a 3D supramolecular structures through π···π stacking interactions. Noticeably, CP 2 contains two kinds of independent units [Zn 2 (cbta)(phen) 2 ] (A) and [Zn 2 (cbta)(phen) 2 (H 2 O)]·4H 2 O (B) to form a 1D+1D structure. A shows 1D double chain based on Zn1, Zn2, which are recognized each other to generate a 2D supramolecular network (A) by hydrogen bonding interactions. While B are ring chains comprised of Zn3, Zn4, which are linked into 2D supramolecular network (B) through π···π stacking interactions. The peculiar structural feature is that the neighboring 2D networks are arranged in a [ABAB···] alternation to form a 3D supramolecular structure through hydrogen bonding interactions and C H···π and C H⋯O week interactions. Especially the (ctba)4- ligands in 1 – 2 adopt three different conformations and coordination modes. The thermal stabilities, XRD, UV, photoluminescence properties of CPs 1–2 were also studied. Remarkably, CPs 1–2 exhibit photocatalytic activities for degradation of dye (MB) under UV light irradiation and show good stabilities toward UV-light photocatalysis. Graphical abstract Two novel d10 metal CPs have been successfully synthesized and structurally characterized. 1 is a 2D network structure based on tetranuclear CdII clusters. 2 contains two kinds of independent units [Zn2(cbta)(phen)2] (A) and [Zn2(cbta) (phen)2(H2O)]·4H2O (B) to form an 1D+1D structure. The peculiar structural feature is that the neighboring A and B chains are arranged in a [ABAB···] alternation to form 3D supramolecular structure through hydrogen bonding interactions and π ... π stacking interactions. In addition, the thermal stability, photoluminescence and photocatalysis of 1–2 were also studied. Image 1 Highlights • Two Cd/Zn CPs with H 4 cbta and phen ligands. • 1 shows a 2D network based on tetranuclear CdII clusters and (cbta)4- ligand. • 2 contains two independent units (A) and (B) to form an 1D+1D structure. • The thermal stabilities and luminescence properties were also studied. • 1–2 exhibit photocatalytic activities for degradation of dye under UV light irradiation. [ABSTRACT FROM AUTHOR]