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Abstract: Two new coordination polymers, [Cu2(oba)2(bpy)2.5] n ·2nH2O (1) and [Cu(bpndc)(bpy)0.5] n (2) (H2oba=4,4′-oxybis(benzoic acid); H2bpndc=benzophenone-4,4′-dicarboxylic acid; bpy=4,4′-bipyridine) were synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. In 1, oba2− anions adopt tridentate and bidentate mode, linking Cu(II) ions into 1D helical chains, and bpy ligands link Cu(II) ions into 1D chains too. These two kinds of chains are interconnected in the Cu(II) nodes, forming a complicated 3D network. In 2, bpndc2− anions adopt tetradentate mode, linking Cu(II) ions into 2D layers. These layers are connected by bpy ligands into a 3D network with small 1D channels. [Copyright &y& Elsevier]

Abstract: Three new lanthanide complexes, [La(HpicO)3(phen)(H2O)] n (1) and Ln3(picO)4(phen)3(H2O)2·HpicO·0.5H2O (Ln=Er (2), Yb (3)) were synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. In complex 1, each La(III) ion is 10-coordinated and HpicO− ligands link the metal ions into 1D zigzag chains. Complexes 2 and 3 are isomorphous, and there are three crystallographically independent Ln(III) ions in the asymmetric unit. The N–H⋯O and O–H⋯O hydrogen bonds and π–π stacking interactions in these complexes result in the formation of 3D supramolecular architectures. [Copyright &y& Elsevier]

Three supramolecular lanthanum coordination compounds of amino acids, with 1,10-phenanthroline (phen), [La2(APA)6(phen)2(H2O)2](ClO4)6(phen)4·2H2O (1), [La2(ABA)6(phen)2(H2O)2](ClO4)6 (phen)6·4H2O (2), and [La2(AHA)4(phen)4](ClO4)6(phen)4·2H2O (3) (APA=3-aminopropionic acid; ABA=4-aminobutanoic acid; AHA=6-aminohexanoic acid) were synthesized and characterized by single crystal X-ray diffraction. The results show that the three coordination compounds are all composed of binuclear coordination cations built by metal-ligand coordination. Through hydrogen bonding and π–π stacking interactions, complex 1 forms a two-dimensional supramolecular sheet structure extending in the (001) plane, complex 2 forms a three-dimensional supramolecular network with many cavities occupied by ClO4− and lattice H2O molecules, and complex 3 forms a two-dimensional supramolecular lamellar structure in the (100) plane. [Copyright &y& Elsevier]

Two novel lanthanide supramolecular coordination polymers, {[Nd2(phth)3(phen)(H2O)]·H2O}n (1, phth=phthalate, phen=1,10-phenanthroline) and {[Ho2(phth)3(phen)(H2O)2]·3H2O}n (2), have been synthesized by hydrothermal method and characterized by X-ray diffraction. The results show that complex 1 crystallizes in triclinic space group P1¯ with a=7.605(2) A˚, b=12.972(4) A˚, c=18.773(6) A˚, α=109.778(5)°, β=91.657(5)°, γ=103.951(5)° and Z=2. Complex 1 has a one-dimentional nano-chain structure and the existence of hydrogen bonds and π–π interactions results in 2D network structure. Complex 2 crystallizes in triclinic space group P1¯ with a=11.695(2) A˚, b=13.488(3) A˚, c=13.761(3) A˚, α=87.09(3)°, β=67.40(3)°, γ=67.41(3)° and Z=2. Complex 2 features a zigzag double-chain and the hydrogen bonds lead to the formation of a three-dimensional network. Both Complex 1 and 2 have two metal environments. [Copyright &y& Elsevier]

Abstract: Three new coordination polymers, [Zn2(CCA)2(bpy)]n·0.5nbpy (1), [Zn(CCA)(bpe)(H2O)]n·0.5nH2O (2) and [Mn(CCA)(bpe)]n·2nH2O (3) (H2CCA = 2-carboxycinnamic acid; bpy = 4,4′-bipyridine; bpe = 1,2-bis(4-pyridyl)ethane) have been synthesized by the hydrothermal reactions and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. Although both complexes 1 and 2 possess 3D metal-organic frameworks, CCA ligands adopt different coordination modes in them. This can be attributed to the introduction of different auxiliary ligands bpy and bpe. In complex 3, CCA ligands link Mn(II) ions into 1D infinite double-strand helical chains and these chains are bridged by bpe to 2D layers. There are hydrogen bonds among the free water molecules, leading to the formation of 1D infinite water chains, which play an important role in the construction of the 3D microporous network. The fluorescent properties of complexes 1 and 2 have also been investigated. [Copyright &y& Elsevier]

Abstract: The reaction of Zn(OAc)2·2H2O and pyrazine-2,6-dicarboxylic acid (H2pzda) with 2,2′-bipyridine (2,2′-bpy), 1,10-phenanthroline (phen) or 1,2-bis(4-pyridyl)-ethane (bpe) gave rise to three new Zn(II) complexes: [Zn(pzda)(2,2′-bpy)(H2O)]·0.5H2O (1), {[Zn(pzda)(phen)(H2O)]·H2O}2 (2) and [Zn2(pzda)2(bpe)(H2O)4]·1.75H2O (3), respectively. For 1, it is a mononuclear structure which is assembled into 3D supramolecular architecture by strong hydrogen bonds (O–H⋯O, O–H⋯N) as well as π–π stacking interactions. In 2, there are two similar mononuclear units, which are further constructed by the hydrogen bonds and π–π stacking interactions into zipper-like supramolecular structure. However, for 3, the bpe ligand bridges two Zn(II) ions cooperated with blocking ligand pzda into binuclear unit, and then the binuclear molecules are alternatively assembled into 3D supramolecular network by hydrogen bonds between the coordinated water molecules and the carboxylate oxygen atoms. The thermal properties of complexes were also investigated. [Copyright &y& Elsevier]

Abstract: Two new mixed-ligands lanthanide coordination polymers, [Ln(Ac)(ip)(H2O)2]·0.5H2O (Ln=La (1); Ln=Eu (2); Ac=acetate; ip=isophthalate) have been synthesized under hydrothermal condition. Single-crystal X-ray analyses show that complexes 1 and 2 are three-dimensional structure in which lanthanide ions are bridged by monocarboxylate ligand, acetate or dicarboxylate ligand, isophthalate. And the central lanthanide ions, La3+ and Eu3+, are both nine-coordinate with oxygen atoms. The thermogravimetric analysis was carried out to examine the thermal stability of the title complexes. And the photoluminescence property of complex 2 was also investigated. [Copyright &y& Elsevier]

Abstract: Three new lanthanide coordination polymers with 1,2,4,5-benzenetetracarboxylic acid, Pr2(betc)2(4,4′-bpyH2)·0.25H2O (1), Ln2(betc)2(4,4′-bpyH2) (Ln=Eu (2), Gd (3)) were hydrothermally prepared. The crystallographic data of 1–3 show that they are isostructural, and possess 3D framework with 1D rhomboid channels, where the 4,4′-bipyridine molecules exist steadily via hydrogen bonds. Meanwhile, a supramolecular structure of (4,4′-bpyH2)2(betc) (4) was also obtained by hydrothermal reaction. The results of 1–4 indicate that 4,4′-bipyridine molecule acting as a template plays an important role in the formation of complexes 1–3, and thus has a synergistic action in the construction of 3D framework with large channels. [Copyright &y& Elsevier]

First examples of lanthanide coordination polymers with 4,4′-biphenyldicarboxylic acid (4,4′-H2bpdc), Ln(4,4′-Hbpdc)(4,4′-bpdc)(H2O)2 (Ln=Pr(1), Eu(2), Gd(3)) and Er(4,4′-bpdc)1.5(H2O)2 (4) were prepared by the solvothermal synthesis. Crystallographic data show that complexes 1–3 are isostructural and each lanthanide(III) ion is coordinated to six 4,4′-Hbpdc ligands, and display 3D sandwich structure with lanthanide ion layers and organic ligand layers alternately linking up with each other. Complex 4 shows different coordination modes of 4,4′-bpdc ligands from 1–3 and each Er(III) ion is attached to four 4,4′-bpdc ligands to construct 3D sandwich structure. The emission spectrum of 2 shows one Eu3+ ion site, which is consistent with the results of the X-ray crystal structure analysis. [Copyright &y& Elsevier]

This paper presents three new lanthanide coordination polymers [Pr2(pim)3(phen)2(H2O)]n·3nH2O (1) (H2pim=pimelic acid; phen=1,10-phenanthroline) and [Ln(Hpim)(pim)(phen)]n·1.5nH2O (Ln=Nd, 2; Er, 3) prepared by the hydrothermal reaction. The structural details of complexes 1, 2 and 3 are reported. In complex 1, the Pr(III) ions are bridged by pim in three modes to form 2D layers. Adjacent layers are assembled by hydrogen bonds and π–π stacking between phen ligands into a 3D network. In complex 2, the Nd(III) ions are connected by pim and Hpim in two modes into 1D chains. Hydrogen bonding and π–π stacking between chains result in a 3D supramolecular structure. Single crystal X-ray diffraction analysis shows that complex 3 is isostructural with complex 2. [Copyright &y& Elsevier]

Reported herein are the hydrothermal synthesis and crystal structures of four lanthanide coordination polymers with nitrilotriacetic acid (H3NTA) [Ln(NTA)(H2O)]n (Ln=La, 1; Pr, 2; Nd, 3; Eu, 4). Despite similar syntheses, compounds 1 to 4 show transformation in coordination mode of NTA and coordination number of Ln3+ duo to lanthanide contraction. The Ln(III) ions in 1 and 2 are nine-coordinated and connected through octadentate bridging ligands (NTA) to form a three-dimensional network. The Ln(III) ions in 3 and 4 are eight-coordinated and bridged by heptadentate bridging ligands (NTA) to form an extended two-dimensional layer structure, which further construct a three-dimensional supramolecular structure via coordination bond and three-centered hydrogen bonding between adjacent layers. [Copyright &y& Elsevier]

Three lanthanide coordination polymers were prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. [Pr2(mBDC)3(phen)(H2O)]n·0.5nH2O (1) (mBDC=isophthalate, phen=1,10-phenanthroline) exhibits two kinds of metal environments (coordination numbers 7 and 8). In complex 1, mBDC ligands adopt the tetradentate (bridging and bridging) coordination mode and connect Pr ions into an undulating layer, and a 3D supramolecular structure is formed via hydrogen bonds between adjacent layers. [Tb4(mBDC)6(phen)]n (2) has three types of metal environments (coordination numbers 6, 7 and 8) and is composed of a 3D network formed by mBDC linking Tb ions via tetradentate (bridging and bridging) and pentadentate (bridging/chelating and bridging) coordination modes. There are two kinds of small quadrilateral channels along the a-axis. [Er4(mBDC)6(phen)]n (3) is isostructural to complex 2. [Copyright &y& Elsevier]

The first series of lanthanide coordination polymers with glutarate (glu) and 1,10-phenanthroline (phen), [Nd2(glu)3(phen)2]n 1, [Tb(glu)(phen)Cl]n 2 and [Ho(glu)(phen)Cl]n 3, have been prepared by hydrothermal reaction and characterised by IR spectra and X-ray crystallography. In complex 1, there are two different conformations for glutarate ligands, the gauche- and anti-forms. Nd(III) ions are bridged by glutarate ligands in three modes to form 2D layer structure. Phen ligands coordinate to Nd(III) ions in chelating mode and protrude from the polymeric layer in two different directions. Two types of π–π interactions exist between two adjacent layers. In complex 2, Tb(III) ions are connected by glutarate ligands into 1D chain structure. Phen ligands coordinate to Tb(III) ions in chelating mode and locate at both sides of the chain. The C–H⋯O, C–H⋯Cl weak hydrogen bonds and π–π stacking interactions between chains result in 3D supramolecular structure. Single-crystal X-ray diffraction analysis shows that complex 3 is isostructural with complex 2. [Copyright &y& Elsevier]

[Eu(ABA)(phen)2(H2O)3](ClO4)3·3phen·4.5H2O (1) and [Eu(Val)(phen)2(H2O)3](ClO4)3·3phen·2H2O (2) are two new europium complexes with amino acids and 1,10-phenanthroline (phen=1,10-phenanthroline, ABA=α-amino butyl acid, Val=l-valine). Their crystal structures were measured by X-ray crystallography. Europium atoms in both complexes are nine-coordinated with bidentate 1,10-phenanthroline and carboxylate anion of amino acids, and water molecules. In the solid state, 1 and 2 have a structure involving aromatic stacking of the coordinated and non-coordinated 1,10-phenanthroline and the oxygen atoms of non-coordinated perchlorate anions being H-bond acceptors connect [Eu(ABA)(phen)2(H2O)3]3+·3phen·4.5H2O or [Eu(Val)(phen)2(H2O)3]3+·3phen·2H2O in their structures. In their interactions, several C–H⋯O bonds play an important role. Owing to their different amino acid ligands and the number of lattice water molecules, there is some difference in their hydrogen bond patterns in 1 and 2. The side chain of l-valine is involved in the formation of C–H⋯O bonds. Hydrogen bond and π–π interactions determine the supramolecular formation of three-dimensional net works of both complexes. [Copyright &y& Elsevier]

Abstract: Three complexes [Mn(pzda)(H2O)2] n (1), [Mn(pzda)(bpy)] n (2) and [Mn(pzda)(phen)(H2O)2] (3) (H2pzda=pyrazine-2,6-dicarboxylic acid, bpy=2,2′-bipyridine, phen=1,10-phenanthroline) were synthesized by the hydro(solvo)thermal reaction and characterized by single crystal X-ray diffraction, elemental analysis, IR spectrum. Complex 1 is a 2D bilayer structure in which each Mn(II) ion is coordinated to two oxygen atoms and two nitrogen atoms from three pzda ligands and two oxygen atoms of two water molecules. Complex 2 is a 3D metal-organic framework structure. Mn(II) is seven-coordinated: four oxygen atoms and one nitrogen atom from three pzda ligands and other two nitrogen atoms from one bpy molecule, displaying a distorted pentagonal bipyramid geometry. While complex 3 is a mononuclear structure in which Mn(II) ion is seven-coordinated to one pzda, one phen, and two water molecules. The complex is connected into a 3D supramolecular network via hydrogen-bonding and π–π stacking interactions. In each of complexes 1–3, pzda ligands adopt different coordination mode. [Copyright &y& Elsevier]