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• Two novel photochromic Zn-MOFs have been successfully prepared. • Compound 1 is layered, while 2 displays unique Anderson-like metal-carboxylate cluster that forms 3D structure. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. By using the flexible viologen carboxylate ligand 1,1′-bis(4-carboxybenzyl)-4,4′-bipyridinium dichloride (H 2 BpybcCl 2) and two kinds of aromatic dicarboxylic acids (1,4-benzenedicarboxylic acid = p -H 2 BDC, 1,2-benzenedicarboxylic acid = σ -H 2 BDC), two novel Zn-MOFs {[Zn 4 (Bpybc) 6 (H 2 O) 12 ]·(p -BDC) 3 ·(OH) 2 ·22H 2 O} n (1) and {KZn 6 (Bpybc) 3 (σ -BDC) 6 ·OH} n (2) have been successfully synthesized. Complex 1 represents the two-dimensional (2D) layered network, while complex 2 displays the unique Anderson-type metal-carboxylate cluster that forms a three-dimensional (3D) framework. It is noticeable that the shape of dicarboxylic acids can have a direct effect on the pattern of the interpenetrated frameworks. In addition, compounds 1 and 2 demonstrate photochromism via reversible electron transfer (ET) and undergo an obvious color transformation owing to the generation of viologen free radicals. Furthermore, we investigated the fluorescent properties under photo modulation and their potential applications in ink-less and erasable printing. Two novel photochromic Zn-MOFs have been successfully synthesized. Compound 1 is layered, while 2 displays unique Anderson-like metal-carboxylate cluster that forms 3D structure. [Display omitted] [ABSTRACT FROM AUTHOR]

• Three compounds containing 1-carboxyethyl-4,4′-bipyridine have been synthesized. • Compounds 1 and 3 exhibit photochromism, while 2 reveals hydrochromism upon heating. • Photo-controlled fluorescence and ink-free erasable printing abilities are discussed. Herein, three compounds containing the neutral viologen derivative, 1-carboxyethyl-4,4′-bipyridine (CEbpy) have been synthesized, (CEbpy)·(H 2 TPDC)·2H 2 O (1) [Co(CEbpy)(TPDC)(H 2 O) 4 ]·3H 2 O (2) and [Cd 3 (CEbpy) 2 (TPDC) 3 ·7H 2 O] n (3) (H 2 TPDC = thiophene-2,5-dicarboxylic acid). Compound 1 is a supramolecular assembly, linked by non-covalent interactions to constitute the donor-acceptor (D-A) system. Compound 2 owns a zero-dimensional (0D) isolated structure in which metal ions are coordinated with CEbpy and fully deprotonated (TPDC)2- ligands. Compound 3 exhibits a three-dimensional (3D) framework of trinuclear metal clusters, where each metal atom forms its own distinct linear one-dimensional (1D) chain along a specific axis. Although the three compounds comprise the same bipyridinium moiety and aromatic acid, their chromic behaviors are different. Compounds 1 and 3 exhibit reversible photochromism, while 2 reveals hydrochromism upon heating. Additionally, photo-modulated fluorescence as well as their potential applications in inkless erasable printing have been studied. [Display omitted] [ABSTRACT FROM AUTHOR]

• Three new 2D coordination polymers have been got by utilizing the carboxybenzyl viologen ligand. • Compounds 1 and 2 exhibit electron transfer photochromism, while compound 3 displays hydrochromism through dehydration. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. By utilizing the carboxybenzyl viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium chloride (HBcbpy·Cl), 1,3,5-benzenetricarboxylic acid (H 3 BTC) and varying different metal ions, three new coordination polymers [Cd(Bcbpy)(HBTC)(H 2 O)·2H 2 O] n (1), [Zn(Bcbpy)(HBTC)(H 2 O)·2H 2 O] n (2) and [Co 2 (Bcbpy) 2 (HBTC) 2 (H 2 O) 2 ·4H 2 O] n (3) have been synthesized and structurally characterized. Compounds 1 and 2 have identical two-dimensional (2D) coordination layered structure, while compound 3 features 2D+2D→2D structure. It is interesting that compounds 1 and 2 exhibit electron transfer photochromism, while compound 3 displays hydrochromism through dehydration. At the same time, considering the high stability and fast photo-response, the photo-modulated fluorescence and the inkless erasable printing capability are investigated. Three CPs derived from 1,3,5-benzenetricarboxylic acid (H 3 BTC)and a neutral viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium (Bcbpy) with different metal ions have been prepared and characterized. Compounds 1 and 2 possess 2D layered structure and exhibit photochromic properties due to the generation of free radicals, while compound 3 owns 2D+2D→2D structure and displays hydrochromism through dehydration and rehydration. [Display omitted] [ABSTRACT FROM AUTHOR]

• Tb-MOF and Sm-MOF based on H 3 ttc were obtained and characterized. • Tb-MOF and Sm-MOF are isomorphic and show a 3D network structure based on terbium/samarium unit. • Tb-MOF can be used as a multifunctional fluorescent probe with high selectivity and excellent sensitivity to detect TNP, Cr 2 O 7 2- and Al3+. • Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. Two three-dimensional metal organic framework {[L n 2 (ttc) 3 ]∙1.5 DMF} n {Ln3+=Tb3+(1), Sm3+(2)} was synthesized by solvothermal reaction of rare earth metal Ln3+ ions and 1-imidazol-1-yl-2,4,6-benzene-tricarboxylic acid (H 3 ttc). The crystal characteristics and composition of the two compounds were confirmed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG), and the single crystal X-ray diffraction confirmed that they are isomorphic. The luminescence and sensing properties of the two compounds were investigated in detail, the Tb-MOF exhibits characteristic emission of Tb3+ through effective sensitization by antenna effect and emits bright green fluorescence under excitation light of 254 nm. Fluorescence experiments show that Tb-MOF has high selectivity and sensitivity for the detection of TNP, Cr 2 O 7 2−, and Al3+ with the limit of detection of 2.89×10−8 mol·L−1, 2.35×10−8 mol·L−1 and 2.69×10−8 mol·L−1, respectively. In addition, possible luminescence quenching mechanisms are discussed. As a result, such a Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. Two three-dimensional metal organic framework {[L n 2 (ttc) 3 ]∙1.5 DMF} n {Ln3+=Tb3+(1),Sm3+(2)} was synthesized by solvothermal reaction of rare earth metal Ln3+ ions and 1-imidazol-1-yl-2,4,6-benzene-tricarboxylic acid (H 3 ttc). The crystal characteristics and composition of the two compounds were confirmed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG), and the single crystal X-ray diffraction confirmed that they are isomorphic. The luminescence and sensing properties show that Tb-MOF hashigh selectivityand sensitivity for the detection of TNP, Cr 2 O 7 2−, and Al3+ with low detection limit. In addition, possible luminescence quenching mechanisms are discussed. Asa result, such a Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. [Display omitted] [ABSTRACT FROM AUTHOR]

The self-assembly of di (p -methylphenyl) oxide (Tol 2 SnO) with 3-(1,3-Dioxo-1 H ,3 H -benzo [ de ]isoquinolin-2-yl)-propionic acid (HL1) and 3-(1,3-Dioxo-1,3-dihydro-isoindol-2-yl)-propionic acid (HL2) produced novel organotin carboxylates (TolSnOL1) 6 (complex 1) and (TolSnOL2) 6 (complex 2) (Scheme 1). Complexes 1 and 2 were characterized by the methods of elemental analysis, IR, 1H, 13C and 119Sn NMR spectroscopy. It has been revealed by single crystal X-ray study that 1 and 2 are mono-organotin carboxylates possessing hexanuclear cage - "Sn 6 O 6 " unit, which presented as a drum. The ligands in the complexes chelate with two tin atoms and adopt bidentate coordination. The molecules of 1 and 2 build their complicated 3D structures via intermolecular π···π interactions and H-bonds. The supramolecular structures of the complexes are discussed in detail. The preliminary fluorescence activity of 1 and antitumor activities of 1 and 2 were also studied. Image 1 • Two novel organotin carboxylates based on amide acid derivatives were synthesized. • Their syntheses, characterizations and crystal structures are discussed in detail. • The preliminary fluorescence and antitumor activities of them were also studied. [ABSTRACT FROM AUTHOR]

Abstract A series of new red emission phosphors Ca 7 Zn 2 (PO 4) 6 : Re3+ (Re3+ = Eu3+, Sm3+, Pr3+) are synthesized by solid state reaction. The crystal structure and microstructure are systematically investigated by X-ray diffraction Rietveld structure refinement, scanning electron microscopy and energy dispersive spectrometer. The photoluminescence properties of Ca 7 Zn 2 (PO 4) 6 : Re3+ (Re3+ = Eu3+, Sm3+, Pr3+) are studied in detail. The results show that Eu3+, Sm3+ or Pr3+ single doped Ca 7 Zn 2 (PO 4) 6 could emit red emissions with dominate peaks at 612 nm, 602 nm and 612 nm, respectively, which are attributed to the characteristic transitions (5D 0 -7F 2 , 4G 5/2 -6H 7/2 and 3P 0 -3H 6) of Eu3+, Sm3+ and Pr3+. The concentration dependent emission spectra of Ca 7 Zn 2 (PO 4) 6 : Sm3+ are studied as well. A charge compensator Li 2 CO 3 is added in Sm3+ doped Ca 7 Zn 2 (PO 4) 6 and the emission intensity is compared with the commercial red phosphor Y 2 O 3 :Eu3+. The room temperature fluorescence lifetimes of Ca 7 Zn 2 (PO 4) 6 : Re3+ (Re3+ = Eu3+, Sm3+, Pr3+) are measured and the average lifetimes are evaluated. Finally, the Commission Internationale de L'Eclairage chromaticity coordinates and their color purity are calculated. Graphical abstract Image 1062 Highlights • Novel red emission phosphors CZP: Re3+ were synthesized for the first time. • Phase purity and microstructure were examined by XRD, SEM and EDS. • Characteristic luminescent property of CZP: Re3+ was investigated. • The detailed emission property of CZP:Sm3+ and CZP:Sm3+, Li+ was studied. • Decay behavior, CIE and color purity of CZP: Re3+ were investigated. [ABSTRACT FROM AUTHOR]

Organotin carboxylates based on an amide carboxylic acid 2-(1,3-dioxo-1 H -benzo[de]isoquinolin-2(3 H )-yl)acetic acid (HL): [(Bn 2 Sn) 2 O 2 L] 2 ·2C 6 H 6 ( 1 ) (Bn = benzyl group) and (Ph 2 Sn)(L) 2 ( 2 ) were synthesized and characterized by elemental analysis, IR, 1 H, 13 C, 119 Sn NMR spectroscopy and X-ray crystallography diffraction analysis. Complex 1 is dimeric carboxylate tetraorganodistannoxane and show a “ladder-like” molecular structure. Complex 2 is a dialkyltin carboxylate monomer possessing crystallographically imposed two-fold symmetry. Ligand in 1 and 2 adopts unidentate and bidentate coordination respectively. Both 1 and 2 form 1D, 2D and 3D supramolecular organizations in the solid state mediated through C H⋯O and π⋯π interactions which are discussed in detail. The luminescent properties and preliminary antitumor activities about this series of complexes were also studied. [ABSTRACT FROM AUTHOR]

• The intramolecular H-bonds (IHBs) for BIHMB, TPHMB1 and TPHMB2 in the S 0 state were strengthened upon light-excitation. • BIHMB, TPHBM1 and TPHMB2 undergo ESIPT via two pathways due to the small difference of ESIPT barrier in two directions. • The fluorescent wavelengths of BIHMB-N and TPHBM1-N TPHMB2-N evidently blue-shifted and red-shifted, respectively. For the sake of systematically probing the atomic substitution effect on luminescent properties and excited state intramolecular proton transfer (ESIPT) behaviors, based on 3-(benzo[ d ]thiazol-2-yl)-2‑hydroxy-5‑methoxy-benzaldehyde (BTHMB), three new compounds BIHMB, TPHBM1 and TPHMB2 were designed by atomic substitution at different positions. For BIHMB, TPHBM1 and TPHMB2, there are two possible ESIPT pathways, and there are two isomers generated and represented by –N or –O. The absorption and fluorescence spectra of BIHMB, TPHBM1 and TPHMB2 were simulated, and their frontier molecular orbitals (FMOs) were analyzed. The atomic substitution can influence their electronic spectra. After investigating the structures, infrared vibrational frequencies and electron densities, we found that the intramolecular hydrogen bonds (IHBs) in the studied compounds are enhanced in the excited (S 1) state. For BIHMB, TPHBM1 and TPHMB2, the EISPT process can occur in two directions since the ESIPT barriers of two directions are not much different. The ESIPT process along the IHB of O 1 H 2 ...O 3 is faster in the order of BIHMB- O > TPHMB2- O > TPHMB1-O, and the ESIPT process along the IHB of O 1 H 2 ...N 4 is slower in the order of BIHMB- N < TPHMB2- N < TPHMB1-N. The stronger the IHB strength, the lower the ESIPT barrier, which has been proved by the potential energy curves. [Display omitted] [ABSTRACT FROM AUTHOR]

• A Zn(II) coordination polymer based on a new ligand is designed and synthesized. • The layered-pillared structure of the polymer is determined by X-ray study. • The large O–thiocarbamate group can prompt the formation of the structure. • Fluorescent property of the polymer is investigated. Continuing our previous strategy for construction of layered–pillared coordination polymer, in this paper, a new O–thiocarbamate–containing ligand H 2 L (5–[(dimethylamino) thioxomethoxy ]–1,3–benzenedicarboxylic acid) has been designed and synthesized to construct a zinc(II)–based metal organic framework, namely [ZnL(4,4′–bpy)] n (1) (4,4′–bpy = 4,4′–bipyridine). Single crystal X–ray diffraction analysis of 1 reveals that the metal ions are bridged by L2– ligands to generate a two–dimensional layer, and the layers are further pillared by 4,4′–bpy to form a three–dimensional framework with a pcu topology. Furthermore, the solid state photoluminescent studies reveal that both H 2 L and polymer 1 display emission bands at 400 nm upon excitation at 325 nm. The average emission life time is 4.27 µs. A layered-pillared Zn(II) coordination polymer is designed and synthesized based on a new O–thiocarbamate –containing dicarboxylic acid ligand. The larger O–thiocarbamate group can properly increase the steric overcrowding, which make the formation of layered-pillared structure possible. The fluorescence of the polymer has also been studied. [Display omitted] [ABSTRACT FROM AUTHOR]

Three novel complexes, namely {[Zn 3 (L) 2 (SO 4 ) 2 (H 2 O) 4 ]·2H 2 O} n ( 1 ), {[Cd(L)(OAc)]} n ( 2 ) and [Hg 2 (L)(I) 3 ] 2 ( 3 ) (HL = N′ - isonicotinoylpyrimidine -2- carbohydrazonamide), have been synthesized and characterized by elemental analyses, infrared spectra and single-crystal X-ray diffraction analyze. The 1D complex 1 and complex 2 , and the binuclear complex 3 are expanded to 3D networkers by the strong hydrogen bonds and π-π stacking interactions. The photocatalytic degradation of methylene blue (MB) results indicate that complexes 1 – 3 are excellent candidates as photocatalysts in decomposing MB with the presence of H 2 O 2 . In addition, the luminescent properties of these three complexes have been studied in the solid state. [ABSTRACT FROM AUTHOR]

Assembly of six isomeric pyridine-diamine-based molecules, N,N′ -bis(pyridin-4-ylmethyl)ethane-1,2-diamine (M1), N,N′ -bis(pyridin-3-ylmethyl)ethane-1,2-diamine (M2), N,N′ -bis(pyridin-2-ylmethyl)ethane-1,2-diamine (M3), N,N′ -bis(pyridin-4-ylmethyl)propane-1,3-diamine (M4), N,N′ -bis(pyridin-3-ylmethyl)propane-1,2-diamine (M5), and N,N′ -bis(pyridin-2-ylmethyl)propane-1,3-diamine (M6), with phosphoric acid (H 3 PO 4 ) in different ratio (1:2 and 1:4), leads to the formation of nine salts, H 2 M1 2+ ·2H 2 PO 4 − ·4H 2 O ( 1 ), H 2 M2 2+ ·2H 2 PO 4 − ·2H 2 O ( 2 ), H 2 M3 2+ ·2H 2 PO 4 − ·2H 2 O ( 3 ), H 4 M1 4+ ·4H 2 PO 4 − ( 4 ), H 4 M2 4+ ·4H 2 PO 4 − ( 5 ), H 4 M3 4+ ·4H 2 PO 4 − ( 6 ), H 2 M4 2+ ·2H 2 PO 4 − ·3H 2 O ( 7 ), 2H 2 M5 2+ ·4H 2 PO 4 − ·2H 3 PO 4 ( 8 ), and H 2 M6 2+ ·2H 2 PO 4 − ( 9 ), which have been characterized by elemental analysis, IR, TG, PL, powder and single-crystal X-ray diffraction. Structural analyses indicate that hydrogen-bonding patterns of H 2 PO 4 − anions, conformation of protonated cations can effectively influence the supramolecular architectures through diverse non-covalent interactions. Hydrous salts 1–3 and 7 present 2D and 3D host-guest supramolecular networks, in which the connection of H 2 PO 4 − anions and water molecules generates diverse tape and layer motifs. H 2 PO 4 − anions in anhydrous salts 4–6 interconnect with each other through hydrogen bonds to form two types of layers, which are joined by discrete H 4 M 4+ cations into 3D inorganic-organic hybrid supramolecular networks. Salts 8–9 also present 2D and 3D host-guest supramolecular networks where the interconnection of H 2 PO 4 − anions and its combination with H 3 PO 4 molecules leads to diverse layers. Luminescent analyses indicate that salts 1–9 exhibit violet and blue emission maximum in the range of 390–467 nm at room temperature. [ABSTRACT FROM AUTHOR]

The first 3-D La III –Sr II heterometallic complex, namely [La 2 Sr(pda) 4 (H 2 O) 4 ] n ·6nH 2 O ( 1 , H 2 pda = pyridine-2,6-dicarboxylic acid), has been successfully synthesized under solvothermal conditions. Single crystal X-ray diffraction analysis reveals that complex 1 features a 3-D porous framework and displays a new topology. The crystal structure can be simplified to a 4,6-connected 3-D network with Schläfli symbol of {3 4 ·4 2 ·8 8 ·9} 2 {3 4 ·4 2 }. The crystals also have been characterized by X-ray powder diffraction, elemental analysis, thermal analysis, and IR spectroscopy. The infrared spectral analysis indicates that complex 1 is a carboxylate coordinated compound, several water molecules exist in the compound. The thermal study shows that there are ten water molecules in the crystal structure. The luminescent property has also been investigated. It shows a blue-purple fluorescence emission. [ABSTRACT FROM AUTHOR]

• The experimental absorption and emission peak are reproduced well. • The intramolecular H-bond in S 1 becomes weaker with the decreasing solvent polarity. • The S 0 e gap gradually increases with the reducing solvent polarity, which causes the gradual blue-shift of the maximum absorption peak. • The larger the polarity of solvent, the easier the ESIPT process. In view of density functional theory (DFT) and time-dependent DFT (TD-DFT) methods, we investigated the influence of solvent polarity on the excited state intramolecular proton transfer (ESIPT) behavior and spectral properties of 2‑butyl‑4-hydroxyisoindoline-1,3‑dione (BHD). In this work, five different solvents were selected: acetonitrile (MeCN), dichloromethane (DCM), tetrahydrofuran (THF), Benzene and n-Heptane. The experimental absorption and fluorescence wavelengths in MeCN were duplicated theoretically, which proved the reliability of the chosen method. The ESIPT process was easy to occur due to the enhanced intramolecular hydrogen bond (H-bond) in the excited state (S 1), which has been confirmed by a series of results related to the H-bond. When the dielectric constant of solvent reduces, the influence of solvent polarity on spectral characteristics and ESIPT behavior included the following aspects: the ground state intramolecular H-bond strength and HOMO-LUMO energy gap became stronger and larger, respectively, while the corresponding parameters of excited state became weaker and smaller, respectively; the forward and reverse ESIPT barrier increased and decreased, respectively. Especially, the H-bond strength of S 1 state and the red-shift value of O 1 H 2 bond were linear with the dielectric constant of solvent. [Display omitted] [ABSTRACT FROM AUTHOR]

One new heterometallic complex [Cd 2 Cu(BTC) 2 (H 2 O) 2 ]⋅2H 2 O ( 1 ) (BTC = benzene-1,3,5-tricarboxylate), has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction techniques. The structure indicates that the complex 1 crystallizes in triclinic, space group P ī, in which, the carboxylate groups of BTC ligand adopt μ 2 –η 1 :η 1 , and μ 2 –η 2 :η 1 coordination modes, bridging Cd(II) and Cu(II) atoms to generate 2D Cd-BTC bilayer then to a (4,6)-connected open 3D framework with 1D channels occupied by guest water molecules. In addition, thermal gravimetric analysis (TGA) and luminescent property of 1 were investigated. [ABSTRACT FROM AUTHOR]

A new cadmium coordination polymer [Cd(DPFE)(adip) 0.5 (NO 3 )] n ( 1 ) has been synthesized hydrothermally from the self-assembly of the Cd 2+ ion with a new π-conjugated rigid ligand DPFE and the adipic acid, where DPFE = 2,7-di(pyridin-4-yl)-9 H -fluorene and H 2 adip = adipic acid. The structure of 1 was full characterized by elemental analysis, FT-IR spectroscopy and single crystal X-ray diffraction. Structural analysis reveals compound 1 is a dinuclear Cd(II) based two-dimensional (4,4) layer and two kinds of strong intramolecular π-π stacking interactions exist between pyridyl rings and benzene rings. In addition, the thermogravimetric analysis and solid–state luminescent properties have also been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers, namely, {[Cd3(L1)2(IP)2(H2O)4]} n (1), {[Cd2(L2)2(IP)2]·(CH3OH)(DMF)} n (2) and [Cd(L3)(IP)] n (3) (H3L1 =benzene-1,2,4-tricarboxylic acid, H2L2 =2,2-bis(4-carboxyphenyl)hexafluoropropane, H2L3 =1,3-phenylenediacetic acid and IP=1H-imidazo[4,5-f][1,10]-phenanthroline), were prepared via self-assembly of pharmaceutical agent IP with cadmium sulfate in the presence of the different backbones of carboxylate linkers under mild conditions. All the polymers possess 2D structural motifs. The rigid tricarboxylate ligand links the metal centers to form a tetranuclear core in 1. In 2, the 2D network with trinuclear cores is further extended into 3D supramolecular arrays through aromatic stacking interactions. Interestingly, IP ligand acts in a tridentate mode via the two N atoms of pyridyl rings and the third N atom of imidazole ring and connects metal atoms into 1D zigzag chain in 3. The structural analysis reveals that the backbones of carboxylates have critical effect on the construction of the complexes. Solid-state luminescent spectra of the Cd(II) complexes indicate intense fluorescent emissions. [Copyright &y& Elsevier]

Abstract: A series of new 3D coordination polymers Ln2(BTC)1.5(H2O)(DMSO) (Lnld>1), Gd(2), Tb(3), Dy(4), Ho(5)) (H4BTC=1,2,4,5-benzenetetracarboxylic acid) have been solvothermal synthesized by the reactions of lanthanide ions with 1,2,4,5-benzenetetracarboxylic acid in a DMSO/H2O solution. These compounds possess the same 3D architectures based on dinuclear lanthanide SBUs {Tb2O4} linked by BTC4− anions and exhibit unprecedented 3D topological nets. Compounds 1 and 3 are strong luminescent materials which display characteristic Eu3+ and Tb3+ emission bands in the visible region. The magnetic properties of 2–5 have also been investigated through the measurement of their magnetic susceptibilities over the temperature range of 2–300K. [Copyright &y& Elsevier]

Abstract: Two new complexes, {[Cd(bimt)(bdc)(H2O)]·2H2O} n (1) and [Cd(bimt)(Hbtc)] n (2) have been synthesized through the self-assembly of Cd(NO3)2·4H2O with unsymmetrical N-heterocyclic ligand 2-((benzoimidazol-yl)methyl)-1H-tetrazole (bimt) and aromatic polycarboxylate acid 1,3-benzenedicarboxylic acid (H2bdc) or 1,3,5-benzenetricarboxylic acid (H3btc). Single crystal X-ray diffraction determination shows that complex 1 possesses an infinite 2-D layered structure with parallelogram grid units. Complex 2 is a 2-D layered structure containing 1-D ladder-like chains linked by the Hbtc2− anions in tridentate bridging fashion. Both complexes are stacked into complicated 3-D frameworks by coordinating bonds and hydrogen bonds in the solid state. In addition, the luminescent properties of both complexes have been investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the influence of spatial extended direction on the resulting structure, three new compounds have been synthesized by the reactions of ZnII or CdII salts and 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL1) or 3,4-bis(pyridin-4-ylmethoxy)benzoic acid (HL2) with two rationally selected multicarboxylate ligands. Without a secondary ligand, an 1D ribbon structure [Zn(L1)2]·H2O (1) furnished, the hydrogen bonds extended the structure to a 2D layer. Employing 4,4′-biphenyldicarboxylic acid (H2bpdc), a 2D layer structure [Zn(L1)(bpdc)0.5] (2) resulted. The use of 1,3,5-benzenetricarboxylic acid (H3btc) led to a 3D compound [Cd2(L2)(btc)(H2O)] (3). It can be observed from the architectures of 1–3 that secondary ligands had great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. [ABSTRACT FROM AUTHOR]

Abstract: A new family of lanthanide with the general formula [Ln(2-Cl-4-FBA)3bipy]2 (Ln=Nd(1), Sm(2), Eu(3), and Ho(4); 2-Cl-4-FBA=2-chloro-4-fluorobenzoate; bipy=2,2′-bipyridine) were synthesized and characterized by elemental analysis, molar conductance, and infrared, ultraviolet and luminescent spectroscopy, single-crystal X-ray diffraction, thermogravimetry and different thermogravimetry (TG–DTG) techniques. These compounds are iso-structural and the lanthanide ions are all nine coordinated via two bidentate chelating, two bidentate bridging and two bidentate chelating-bridging modes. Under excitation, the europium complex exhibited characteristic red fluorescence of Eu3+ ion at room temperature. The non-isothermal kinetics was investigated by using NL-INT and Popescu methods. The mechanism functions of the first decomposition step of the title complexes were determined. Meanwhile, the thermodynamic parameters (ΔG≠, ΔH≠ and ΔS≠ ) were also calculated. [Copyright &y& Elsevier]

Abstract: A series of new lanthanide coordination polymers, with the formula [Ln(bipy)(glut)(NO3)] (Ln=Eu (1), Tb (2), Sm (3), Pr (4); bipy=2,2′-bipyridine; H2glut=glutaric acid), have been synthesized under the hydrothermal condition and characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction, and single-crystal X-ray diffraction. Structural analyses reveal that all four complexes are isostructural and crystallized in monoclinic system, P21/c space group. For these complexes, the Ln3+ are all linked through glutaric acid ligands to form 1D chain-like polymeric structures, and bipy and are coordinated on two sides of the chains. The thermogravimetric analysis of 1 and photoluminescent properties of 1 and 2 are discussed in detail. [Copyright &y& Elsevier]

Abstract: A novel photoluminescent coordination framework Pb(qlc)2 (Hqlc=quinoline-6-carboxylic acid) (1), has been obtained through self-assembly of Pb(NO3)2 with Hqlc ligand and characterized by IR spectra and elemental analysis. Single-crystal X-ray diffraction analysis reveals that the complex adopts a (4,4) topological layer structure. Solid state emission spectrum of the compound exhibits blue-violet luminescence upon exposure to ultraviolet radiation. [Copyright &y& Elsevier]

Abstract: Two novel coordination polymers associated with indium and cadmium ions respectively, {[In(TCA)(OH)(H2O)]} n (1) and {[Cd(TCA)(H2O)3]·4H2O} n (2) (H2TCA=thiophene-2,5-dicarboxylic acid), were prepared under hydrothermal conditions, and characterized by the single-crystal X-ray diffraction, element analysis, IR and luminescence spectra. Compound 1 displayed an interesting 2D lattice structure, consisted of indium ions, OH− anions and TCA ligands. In 2, seven coordinated cadmium ions were bridged by TCA ligands to generate 1D chain. The luminescent properties for 1, 2 and the TCA ligand have also been explored. [Copyright &y& Elsevier]

Abstract: A new family of lanthanide complexes with the general formula {[Ln(nphth)(Hnphth)(H2O)3·H2O]2} n (Ln=Pr, Eu, Gd, Tb, Dy, 1–5 and H2nphth=3-nitrophthalic acid) have been synthesized under hydrothermal condition and four of them have been characterized by single-crystal X-ray diffraction and spectroscopy. These compounds are isostructural and the lanthanide ions are all nine coordinated and europium complex emits characteristic red fluorescence of Eu3+ ions at room temperature while other three lanthanide complexes exhibit the particular emission ascribed H2nphth ligand, which suggest that the different energy transfer process takes place. [Copyright &y& Elsevier]

Abstract: Two novel three-dimensional d10 metal coordination polymers [Zn2(pydc)2(DMF)3] n (1) and [Cd2(pydc)2(H2O)] n (2) (H2pydc=pyridine-3,4-dicarboxylic acid, DMF=N,N-dimethylformamide) have been synthesized under solvothermal and hydrothermal conditions, and characterized by elemental analysis, IR, TG analysis and single crystal X-ray diffraction. Compound 1 exhibits a complex three-dimensional framework containing one-dimensional elliptic channels occupied by coordinated DMF molecules. In complex 2, adjacent sheets constructed by carboxyl-bridged Cd–O–Cd chains are pillared by pydc ligands into a three-dimensional network. From a topological point of view, the two three-dimensional nets display (3,4)-connected (6.82)2(6.85) and 4-connected (4.85)(42.6.83)2(43.62.8) topologies, respectively, which are unprecedented within coordination frames. Furthermore, both compounds show intense fluorescent emissions upon photoexcitation at room temperature. [Copyright &y& Elsevier]

Abstract: Two novel lanthanide coordination polymers [Sm(Hdipic)(dipic)(H2O)2·4H2O] n (1) (H2dipic=2,6-pyridinedicarboxylic acid) and [Dy(Hdinic)(dinic)(phen)(H2O)·H2O] n (2) (H2dinic=2,5-pyridinedicarboxylic acid) have been synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction. The results reveal that both of them form a chain-like one-dimensional structure. The photophysical properties for the two complexes have been also reported. Complex 1 shows the characteristic luminescence of central Sm3+ while complex 2 exhibits the particular emission ascribed H2dinic ligands, which suggest the different energy transfer process takes place. [Copyright &y& Elsevier]

Abstract: Two new two-dimensional (2D) layered d10 metal coordination polymers, [M(PDB)(2,2′-bpy)]n (M=Zn2+ (1) and Cd2+ (2), PDB=pyridine-3,4-dicarboxylate), have been prepared by hydrothermal reaction and characterized by IR, TGA, and single-crystal X-ray diffraction analysis. Compounds 1 and 2 both exhibit puckered hexagonal (6,3) sheets and represent the first examples of 2D structures formed by PDB and chelate heterocyclic ligand. Furthermore, both of them show intense luminescent properties at room temperature. [Copyright &y& Elsevier]

Two new coordination polymers, namely, [Zn 2 (L) 2 (H 2 O) 4 ] n ·nH 2 O (1) and [Zn 2 (L) 2 (H 2 O) 2 ] n ·nH 2 O (2) (H 2 L = 5-(1H-1,2,4-triazol-1-yl)-1,3-benzenedicarboxylic acid), were constructed by changing pH under hydrothermal condition and characterized by elemental analysis, IR and single crystal X-ray diffraction. Compound 1 is formed at pH 3.5, which displays a 3-connected two-dimensional (2D) layer structure with the Schläfli symbol of 63 and are further extended into a three-dimensional (3D) supramolecular network by inter-molecular hydrogen bonds and π ... π stacking interactions. While at pH 5.5, compound 2 displays a unusual 3D coordination network which exhibits an intriguing self-interpenetrating (3,6)-connected topological net with the Schläfli symbol of (4.62) 2 (42.69.83.10). Interestingly, Compounds 1 and 2 were obtained in the similar reaction conditions. The structural differences of two compounds give some insights into the effect of pH on the construction of coordination polymers. Additionally, the thermal stabilities and photoluminescence properties of 1 and 2 were also studied. Two new zinc coordination polymers based on carboxylate functionalized triazole derivative ligand have been synthesized by changing pH under hydrothermal condition. Interestingly, Compound 1 is formed at pH 3.5, which displays a 3-connected two-dimensional (2D) layer structure with the Schläfli symbol of 63. While at pH 5.5, compound 2 displays a unusual 3D coordination network which exhibits an intriguing self-interpenetrating (3,6)-connected topological net with the Schläfli symbol of (4.62) 2 (42.69.83.10). Additionally, photoluminescence properties of 1 – 2 have been investigated. Image 1 • Two new zinc coordination polymers were constructed by changing pH. • Compound 1 shows a 3-connected 2D layer structure. • Compound 2 shows a unusual self-interpenetrating 3D coordination network. • They possess high thermal stability. [ABSTRACT FROM AUTHOR]