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Self‐assembly of transition metal ions with different N‐donor ligands and 3,3′‐azodibenzoic acid (3,3′‐H2ADB) yielded five novel metal‐organic frameworks. All the 3,3′‐ADB2– anions got oxidized into 3,3′‐AO2DB2– and 3,3′‐AODB2– under solvothermal conditions. Compound 1 has a 3D 6‐connected pcu architecture based on [Mn3(COO)6] SBU. Compound 2 exhibits 3D threefold interpenetrating framework based on paddlewheel [Mn2(COO)4] SBU with 41263 topological configuration. Compound 3 bears zigzag double chains, which are then connected by π–π stacking interactions into 2D porous structure. Compound 4 features 2D network with self‐penetrating feature. Compound 5 exhibits a fivefold interpenetrating architecture with dia type. Magnetic measurements show that 1, 2 and 5 exhibit antiferromagnetic behavior. In addition, compound 3 displays significant adsorption towards methylene blue in aqueous solution. Thermogravimetric analyses for 1–5 and the luminescence properties of 3 and 4 have also been investigated. [ABSTRACT FROM AUTHOR]

Two type lanthanide complexes obtained by salen-type ligand N,N'-ethylenebis(salicylideneimine) (HL) and N,N'-ethylene-bis(3-methoxysalicylideneimine) (HL) have been isolated. They are 2D coordination polymer [Yb(HL)(NO)] ( 1), mononuclear Ln(HL)(NO) [Ln = Sm ( 2), Ho ( 3)]. The structures of 1- 3 were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. [ABSTRACT FROM AUTHOR]

A novel unexpected 1D coordination polymer Nd(Nphgly)(1,2-BDC)(H2O)·2H2O (1) containing simultaneously N-phthaloylglycine (Nphgly) and benzene-1,2-dicarboxylic acid (1,2-BDC) ligands has been prepared under the solvothermal conditions. In situ solvothermal aminolysis reaction occurred at benzene-1,2-dicarboxylic acid and glycine when they reacted with neodymium salts. Furthermore, the magnetic and luminescent properties of 1 were studied. [ABSTRACT FROM AUTHOR]

Herein, a series of ionic mononuclear Cu(I) complexes, [Cu(phen)(bdppmapy)]Cl (1a), [Cu(phen)(bdppmapy)]Br (2a), [Cu(phen)(bdppmapy)]I (3a), [Cu(phen)(bdppmapy)]SCN (4a), [Cu(Dpq)(bdppmapy)]Cl (1b), [Cu(Dpq)(bdppmapy)]Br (2b), [Cu(Dpq)(bdppmapy)]I (3b) and [Cu(Dpq)(bdppmapy)]SCN (4b) {phen = [1,10]phenanthroline; Dpq = pyrazino[2,3-f][1,10]-phenanthroline; bdppmapy = N,N-bis((diphenylphosphino)methyl)-2-pyridinamine} have been synthesized and characterized by using IR, NMR, elemental analysis, single crystal X-ray diffraction analysis, fluorescence spectroscopy methods, and UV-vis and terahertz (THz) time-domain absorption spectroscopy. Their crystal structures were elucidated by X-ray crystallography and their photophysical properties were investigated in detail. All the above complexes exhibit a 1D to 3D supramolecular structure which is linked together by intermolecular weak interaction forces and hydrogen bonds. By regulating ligands and anions, the emission wavelengths of these complexes are quite different in the range from 533 nm to 604 nm. Theoretical calculations and photophysical properties indicate that luminescence is derived from metal-to-ligand charge transfer (MLCT) excited states. In the meantime, the results of calculations show that the stabilization of the increased conjugation of the ligand-based π* orbital is ascribed to the observed bathochromic-shift in the MLCT transitions. [ABSTRACT FROM AUTHOR]

On the basis of the 3-(pyrazin-2-yl)-1H-pyrazole-5-carboxylic acid (H2L) ligand, four new polymers [Cu2(L2−)2] (1), [Zn3(L2−)2(H2O)4Cl2]n (2), [Pb(HL−)Cl]n (3), and {[Ni(L2−)(H2O)]·(H2O)}n (4) have been synthesized under solvothermal conditions. Polymer 1 possesses a discrete (0D) binuclear structure, which is further formed into a three-dimensional (3D) supramolecular structure by hydrogen bonding and π⋯π stacking interactions. Polymers 2 and 3 display one-dimensional (1D) infinite chain structures, which further extend into 3D supramolecular structures through hydrogen bonding interactions. Polymer 4 features two-dimensional (2D) layers which can form a 3D supramolecular architecture via interlayer hydrogen bonds. The ligand in the four polymers adopts different coordination modes for constructing versatile structures. Moreover, luminescence sensing study shows that polymer 2 is a promising luminescent sensor for the detection of Cu2+, Co2+ and Fe3+via drastic luminescence quenching in aqueous solution with high efficiency. The quenching constants KSV for Cu2+, Co2+ and Fe3+ are 6.35 × 103 M−1, 8.70 × 103 M−1 and 1.62 × 104 M−1, respectively. What's more, 1–4 with electrochemical luminescence (ECL) properties show high intensity in N,N-dimethylformamide (DMF) solution and high thermal stability. [ABSTRACT FROM AUTHOR]

In acidic solution, a serials of water-soluble coordination polymers (CPs) were isolated as zonal 1D-CPs 1,3-propanediaminetetraacetato lanthanides [ Ln (1,3-H 3 pdta)(H 2 O) 5 ] n ·2Cl n ·3 n H 2 O [ Ln =La, 1 ; Ce, 2 ; Pr, 3 ; Nd, 4 ; Sm, 5 ] (1,3-H 4 pdta=1,3-propanediaminetetraacetic acid, C 11 H 18 N 2 O 8 ) in high yields. When 1 eq. mol potassium hydroxide was added to the solutions of 1D-CPs, respectively, two 1D-CPs [Ln(1,3-H 2 pdta)(H 2 O) 3 ] n ·Cl n ·2 n H 2 O [ Ln =Sm, 6 ; Gd, 7 ] were isolated at room temperature and seven 2D-CPs [ Ln (1,3-H 2 pdta)(H 2 O) 2 ] n ·Cl n ·2 n H 2 O [ Ln =La, 8 ; Ce, 9 ; Pr, 10 ; Nd, 11 ; Sm, 12 ; Eu, 13 ; Gd, 14 ] were isolated at 70 °C. When the crystals of 1–4 were hydrothermally heated at 180 °C with 1–2 eq. mol potassium hydroxide, four 3D-CPs [ Ln (1,3-Hpdta)] n · n H 2 O [ Ln =La, 15 ; Ce, 16 ; Pr, 17 ; Nd, 18 ] were obtained. The two 2D-CPs [ Ln (1,3-Hpdta)(H 2 O)] n ·4 n H 2 O (Sm, 19 ; Eu, 20 ) were isolated in similar reaction conditions. With the increments of pH value in the solution and reaction temperature, the structure becomes more complicated. 1–5 are soluble in water and 1 was traced by solution 13 C{ 1 H} NMR technique, the water-soluble lanthanides 1 and 5 show catalytic activity to ester hydrolysis reaction respectively, which indicate their important roles in the hydrolytic reaction. The europium complexes 13 and 20 show visible fluorescence at an excitation of 394 nm. The structure diversity is mainly caused by the variation of coordinated ligand in different pH values and lanthanide contraction effect. Acidic conditions are favorable for the isolations of lanthanide complexes in different structures and this may helpful to separate different lanthanides. The thermal stability investigations reveal that acidic condition is favorable to obtain the oxides at a lower temperature. [ABSTRACT FROM AUTHOR]

By using different N-donor organic species as additional auxiliary ligands with structure-directing roles, four three-dimensional (3D) calcium-based coordination complexes, [Ca(dbt)(H2O)]n1, [Ca(H-dbt)2(5,5′-dmbpy)2]n2, (4,4′-bpy)0.5[Ca(dbt)(H2O)2]n3, and (H2-dib)[Ca3(dbt)4(H2O)4·2H2O]n4 (H2-dbt = 2,5-dibromoterephthalic acid, 2,2′-bpy = 2,2′-bipyridine, 5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine, 4,4′-bpy = 4,4′-bipyridine, dib = 1,4-di(1H-imidazol-1-yl)benzene), have been successfully synthesized under similar solvothermal conditions and structurally characterized. The organic amine molecules play different roles in the formation of four different metal–organic skeletons with diverse structural topologies, in which complexes 1–3 are neutral, and 4 comprises a negatively charged framework with diprotonated dib as the counterion. Complex 1 features a 3D (6,6)-connected framework structure composed of edge-sharing 1D Ca–O–Ca inorganic chains and dbt ligands. The 2,2′-bpy molecule plays an important role in the synthesis of 1 as the structure-directing agent (SDA). Complex 2 shows a 3D 2-fold interpenetrated diamondoid framework (dia, 66) formed by single metal nodes via linear H-dbt anions and bidentate chelating 5,5′-dmbpy ligands, while complex 3 exhibits a 3D noninterpenetrated pcu network with {412·63} topology constructed from binuclear [Ca2(CO2)4] secondary building units and two types of dbt ligands, in which 4,4′-bpy molecules are ordered within the 3D neutral calcium-based framework as template and space filling agents. Complex 4 is a unique (4,4,4,4,5)-connected 5-nodal topology net, in which the diprotonated dib molecules provide space filling to balance the negatively charged framework. In addition, the thermal stability and the fluorescence properties of complexes 1–4 have been investigated. [ABSTRACT FROM AUTHOR]

Two rare 2D Ga/In-based coordination polymers in which one metal center coexists with three distinct aromatic ligands were synthesized. Helical channels along the 21 screw axis are exhibited to form a hcb net. The compounds exhibit tunable fluorescence from blue, green, white to yellow light by varying the temperature and solvents. [ABSTRACT FROM AUTHOR]

Two new lanthanide coordination polymers formulated as [Ln(BDC)(DMF)(HO)] [Ln = Tb ( 1), Gd ( 2)] [HBDC = 1,4-benzenedicarboxylic acid, DMF = N,N′-dimethylformamide] were synthesized under solvothermal conditions. The coordination polymers were characterized by IR spectroscopy, elemental analysis and X-ray single-crystal diffraction. The two coordination polymers are isostructural and exhibit twofold interpenetrating pcu three-dimensional open frameworks constructed by tetradentate ligand of HBDC. The fluorescence properties of 1 and 2 were investigated at 298 or 77 K both in solid state and in CHCl solvent dispersed as suspensions. Coordination polymer 1 exhibits characteristic Tb ions emission transitions of D → F ( J = 6-2) at 77 or 298 K both in the solid-state and in CHCl solvent. Moreover, the vibrational structure of 1 is more defined at 77 K, which exhibits another two D → F and D → F transitions more than that at 298 K. The lifetimes of 1 are longer at 77 K (915.2 μs in the solid state and 874.11 μs in the CHCl solvent) than that at 298 K (866.31 μs in the solid state and 801.04 μs in the CHCl solvent), which may be caused by the increase of radiative rate and decrease of non-radiative rate at low temperature. The singlet excited state (28,653 cm) and the lowest triplet energy level (23,641 cm) of HBDC ligand were calculated based on the UV-Vis absorbance edges of ligand and the phosphorescence spectrum of Gd coordination polymer ( 2) at 77 K, showing that the effective extent of energy transfer from HBDC ligand to Tb ion. Finally, thermal behaviors of the two coordination polymers were studied by thermogravimetric analysis, which exhibit thermal stability to 250 °C. [ABSTRACT FROM AUTHOR]

Two coordination polymers, Zn7O(cpda)3(OH)3 ( 1) and [Tb(H2cpda)(Hcpda)(H2O)] ·(H2O) ( 2) (H3cpda = 5-(4-carboxyphenyl)-2, 6-pyridinedicarboxylic acid), were synthesized and characterized by elemental analysis, FTIR spectroscopy, TGA, PXRD, and single-crystal X-ray diffraction. Complex 1 has a 3D framework structure with high thermal stability and complex 2 exhibits 1D chain structure. Luminescent measurements indicate that complex 1 shows strong ligand-to-metal charge transfer (LMCT) luminescence, while complex 2 exhibits the characteristic emission of Tb3+ ions. [ABSTRACT FROM AUTHOR]

A series of novel lanthanide coordination polymers havebeen successfullysynthesized under hydrothermal or solvothermal conditions, namely,[Eu2(2,4′-bpdc)2(OH)(NO3)(H2O)3]n(1), [Ln(2,4′-bpdc)(1,4-bdc)0.5(DMF)-(H2O)·H2O]n[Ln = Eu (2); Ln = Pr (3); Ln = Nd (4)], [Ln(2,4′-bpdc)(DMF)2NO3]n[Ln = Eu (5); Ln = Nd (6); Ln = Gd (7)], and[Eu(2,4′-bpdc)(2,4′-Hbpdc)(H2O)]n(8), (2,4′-H2bpdc= 2,4′-biphenyldicarboxylic acid, 1,4-H2bdc = 1,4-benzenedicarboxylicacid, and DMF = N,N′-dimethylformamide).X-ray crystallographic studies reveal that 1featuresa three-dimensional (3D) framework with 45topology. 2–4, which are isostructural and synthesizedby using a mixture of 2,4′-H2bpdc and 1,4-H2bdc, exhibit two-dimensional (2D) (3,4)-connected net structures. 5–7show 2D layered structures containingdouble helix chains (Δ and Λ) with 44topology. 8possesses a 2D layered structure containing (4,6)-connectednetworks, which are connected by means of infinite zigzag chains linkedby 2,4′-bpdc2–and 2,4′-Hbpdc–anions. Furthermore, steady-state and time-resolvedspectroscopic measurements reveal that the four Eu(III) complexes, 1, 2, 5, and 8, exhibitremarkable red luminescence emissions with lifetimes at the millisecondscale. Complexes 4and 6display characteristicluminescent properties for Nd(III) in the near-infrared region. Thesinglet state and the lowest triplet level of ligand 2,4′-H2bpdc were calculated on the basis of the UV–vis absorbanceedges of ligand and the phosphorescence spectrum of Gd(III) complex 7. The energy transfer mechanisms in the lanthanide polymersare described and discussed. [ABSTRACT FROM AUTHOR]