3D Lanthanide Coordination Polymers Research Articles

A series of isostructural Ln-based coordination polymers: Crystal structure, luminescence sensing and color tuning

Compared with traditional detection methods, fluorescent sensors have many advantages in identifying metal ions. Herein, a new series of three-dimensional (3D) lanthanide coordination polymers (CPs) [Eu3(FDA)4(DMSO)2(NO3)(H2O)2]n (CP-1), [Tb3(FDA)4(DMSO)2(NO3)(H2O)2]n (CP-2) and [Eu3xTb3(1-x)(FDA)4(DMSO)2(NO3)(H2O)2]n (Eu/Tb-CP) based on 2,5-furandicarboxylic acid (H2FDA) were synthesized. Single-crystal X-ray diffraction indicated that both the CP-1 and CP-2 were isomorphic with a topology of {42.5}2{44.510.69.74.8} based on trinuclear second building units to form a 3D framework. Luminescence sensing experiments revealed that CP-1 has a good selection and recognition effect on Fe3+ (Ksv = 3.3 × 104 M−1, limit of detection (LOD) = 2.31 μM) and shows great potential as a luminescence sensor. Additionally, color tuning could be achieved by doped Eu3+ and Tb3+ into the reaction mixtures using the synergistic effect of their luminescent centers.

2D lanthanide coordination polymers as multi-responsive luminescence sensors for selective and sensitive recognition of Cr(VI)/MnO4− anions and broad-spectrum detection of antibiotics

Three new Ln(III)-CPs, {[Ln2(HL)2(H2O)2]·H2O}n (Ln=La (1), Eu (2) and Tb(3); H4L ​= ​1,1'-(ethane-1,2-diyl)bis(1H-imidazole-4,5-dicarboxylic acid)) were hydrothermally synthesized and characterized by elemental analyses, IR, TG, PXRD and single-crystal X-ray diffraction. These isostructural CPs display 2D layer-like structures with a TiS2 topology constructed from inter-connected cage-like SBBs. The Eu-CP and Tb-CP exhibit characteristic luminescent emissions based on metal ions and possess selective recognition ability toward Cr(VI) and MnO4− ions in aqueous solution. They can also act as broad-spectrum fluorescent probes to detect common antibiotics. Furthermore, the fluorescence quenching mechanisms of two CPs were also studied in detail by combination of the PXRD patterns, UV–vis absorption spectra and theoretical calculations.

2d Lanthanide Coordination Polymers as Multi-Responsive Luminescence Sensors for Selective and Sensitive Recognition of Cr(Vi)/Mno4– Anions and Broad-Spectrum Detection of Antibiotics

2d Lanthanide Coordination Polymers as Multi-Responsive Luminescence Sensors for Selective and Sensitive Recognition of Cr(Vi)/Mno4– Anions and Broad-Spectrum Detection of Antibiotics

Crystal structures and thermodynamic properties of lanthanide complexes with 2,6-dimethylbenzoic acid and 2,2′:6′,2′′-terpyridine

Two 2D lanthanide coordination polymers Ln2(2,6-DMBA)5(terpy)2(NO3)(H2O)2 (Ln = La(1), Pr(2); 2,6-DMBA = 2,6-dimethylbenzoic; terpy = 2,2′:6′,2′′-terpyridine) were successfully prepared through conventional solution method at room temperature. Their structures were identified by IR, XRD, single crystal X-ray diffraction and elementary analysis. These means show that complexes 1–2 are isomorphous. The two identical central metal ions of the binuclear complex have different coordination environments and coordination numbers. Thermogravimetric analyses (TGA) were researched by TG/DSC-FTIR, and showed multi-step decompositions. The heat capacities of complexes 1 and 2 were determined by DSC from 260.15 K to 374.15 K. Furthermore, based on the fitted polynomial and thermodynamic equation, the thermodynamic parameters values of the complexes 1 and 2 were obtained.

2D Lanthanide Coordination Polymers: Synthesis, Structure, Luminescent Properties, and Ratiometric Sensing Application in the Hydrostable PMMA-Doped Hybrid Films

Three LnIII coordination polymers, [LnL(NO3)3]n∙2C4H8O2 (LnL, Ln= Nd, NdL; Eu, EuL; Tb, TbL) based on a asymmetric poly-monodentate ligand L, which has abundant branched end groups for chelating Ln...

Synthesis of eight isostructural 2D lanthanide coordination polymers assembled by rigid furan-2,5-dicarboxylic acid and flexible adipic acid as linkers and exploration of luminescent Eu/Tb polymers as efficient and sensitive sensors for nitroaromatic compounds

Eight isostructural coordination polymers were synthesized by a solvothermal method. The luminescent Eu/Tb polymers function as efficient sensors for nitroaromatics via turn-off mode.

2D lanthanide coordination polymers constructed from semirigid ligand 4-(pyridin-3-yloxy)-phthalic acid: Synthesis, structure and luminescence

Three new compounds (Ln–CPs) [Ln(PPDA)(C2O4)0.5(H2O)2]n·nH2O (Ln = Tb (1), Eu (2) and Gd (3)) were synthesized based on semirigid ligand 4-(pyridin-3-yloxy)-phthalic acid (H2PPDA) under solvothermal conditions. Ln–CPs 1–3 exhibit isomorphic 2D layered network with rhombic windows. Notably, oxalic acid in the resulting framework is formed by in situ reaction under solvothermal and acidic conditions. Solid state luminescent studies indicate that 1 and 2 show characteristic green and red emissions of the corresponding Ln3+ ions, respectively, while 3 exhibits blue emission arising from PPDA2− ligand. Then, by adjusting the co-doping ratio of different Ln3+ ions into the well-defined host framework, a series of codoped Ln–CPs Eu3+-doped 1 and Eu3+, Tb3+-doped 3 are synthesized, showing tunable luminescence emissions including white-light emitting.

Unprecedented homochiral 3D lanthanide coordination polymers with triple-stranded helical architecture constructed from a rigid achiral aryldicarboxylate ligand

Luminescence and second harmonic generation activity of a series of homochiral 3D Ln-CPs were studied.

Synthesis, structure and photoluminescence of 3D lanthanide coordination polymers based on 2-(3,5-dicarboxybenzyloxy) benzoic acid

A series of novel three-dimensional lanthanide coordination polymers with the building block [Ln2(dcob)6(DMF)2(H2O)2], [Ln(dcob)(DMF)(H2O)]n [Ln = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Er (8), H3dcob = 2-(3,5-dicarboxybenzyloxy) benzoic acid, DMF = N,N-dimethylformamide], were prepared under hydrothermal conditions and characterized by X-ray single-crystal diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. 3, 4, 6 and 7 show luminescence of the trivalent lanthanides.

Structure variation and luminescence of 3D, 2D and 1D lanthanide coordination polymers with 1,3-adamantanediacetic acid

We report the synthesis of 3D Ln-CPs [Tb2(ADA)3]n (1a, H2ADA = 1,3-adamantanediacetic Acid), 2D Ln-CPs [Ln2(ADA)3(dmp)2]n·2EtOH·H2O, (Ln3+ = Eu3+, 2a; Gd3+, 2b; Tb3+, 2c; dmp = 4,7-dimethyl-1,10-phenanthroline), and 1D Ln-CPs [Ln(ADA)(HADA)(H2O)]n (Ln3+ = Eu3+, 3a; Gd3+, 3b; Tb3+, 3c), by introducing the ligand H2ADA. The Ln-CPs are characterized by single-crystal X-ray diffraction, PXRD, TGA, elemental analysis and FT-IR. Structure variation is analyzed and suggestions are given for obtaining different types of structures. Luminescence spectra, lifetimes and quantum yields (QYs) are investigated.

3D isomorphous lanthanide coordination polymers displaying magnetic refrigeration, slow magnetic relaxation and tunable proton conduction

Four new isostructural lanthanide-based three-dimensional (3D) coordination polymers (CPs), {[Ln4(OH)4(L)2(H2O)8]·4.6H2O·1.4CH3CN}n (Ln3+ = Gd3+ (1), Dy3+ (2), Ho3+ (3) and Er3+ (4)), have been constructed using a sulfonate-carboxylate-based ligand (Na2H2L = disodium-2,2'-disulfonate-4,4'-oxydibenzoic acid) and the corresponding lanthanide metal(iii) nitrates. All the CPs 1-4 contain [Ln4(μ3-OH)4]8+ cubane-like cores interconnected through L4- ligands to give rise to 3D coordination frameworks with 1D hydrophilic channels along the crystallographic c direction. From the topological perspective, the underlying 3D nets of the CPs can be classified as a 3,6,6-c net with an undocumented topology. Magnetic studies display that CP 1 exhibits a magnetocaloric effect with a significant magnetic entropy change (-ΔSm) = 34.6 J kg-1 K-1 for ΔH = 7 T at 3 K. CP 2 shows field-induced slow magnetic relaxation properties with energy barrier (Ueff/kB) = 30.40 K and relaxation time (τ0) = 2.47 × 10-7 s. Theoretical calculations have been performed to corroborate the magnetic exchange coupling constant value for CP 1 and to obtain a deeper understanding of the field-induced slow magnetic relaxation behavior of CP 2. Impedance analyses display high values of proton conductivity which reach 2.02 × 10-6, 2.96 × 10-6, 4.56 × 10-3 and 6.59 × 10-3 S cm-1 for CPs 1-4, respectively at high temperature (>75 °C) and 95% relative humidity (RH) in the order CP 1 < CP 2 < CP 3 < CP 4. Notably, the proton conductivities for CPs 3 and 4 are a few orders of magnitude higher than those of CPs 1 and 2 (10-3 S cm-1vs. 10-6 S cm-1), and the conductivity increases periodically following the decreasing order of ionic radius (Gd3+ > Dy3+ > Ho3+ > Er3+). This demonstrates the effective employment of the lanthanide contraction strategy to tune proton conductivity while preserving proton-conducting pathways.

Temperature-dependent 3D structures of lanthanide coordination polymers based on dicarboxylate mixed ligands

Four families of fourteen three-dimensional (3D) lanthanide coordination polymers (CPs) with dicarboxylate mixed ligands have been synthesized hydrothermally at different temperatures.

A series of 3D lanthanide coordination polymers decorated with a rigid 3,5-pyridinedicarboxylic acid linker: syntheses, structural diversity, DFT study, Hirshfeld surface analysis, luminescence and magnetic properties.

Single crystal X-ray diffraction studies reveal the formation of six new coordination polymers (CPs) with the general formulas [Dy(3,5-pdc)(3,5-pdcH)(H2O)2]n·nH2O (1), [Pr2(3,5-pdc)3(H2O)2]n·2n(H2O) (2), [Sm2(3,5-pdc)3(H2O)3]n·nH2O (3), {[Eu2(3,5-pdc)3(H2O)3(CH3CHO)]n·n[2(H2O)(DMF)]} (4), {[Gd2(3,5-pdc)3 (H2O)2]n·2nH2O} (5) and [Er(3,5-pdc)(adip)0.5(H2O)]n (6) (where 3,5-pdc2- = fully deprotonated; 3,5-pdcH- = partially deprotonated 3,5-pyridinedicarboxylic acid; adip2- = fully deprotonated adipic acid; and DMF = dimethylformamide) by solvothermal self-assembly of lanthanide ions with rigid 3,5-pyridinedicarboxylic acid as a linker and adipic acid as an auxiliary flexible spacer (only coordinated in CP 6). CPs 1 and 2 crystallize in the triclinic P1[combining macron] space group, whereas CPs 3, 4 and 6 crystallize in the monoclinic P21/n, P21/c and C2/c space groups, respectively. CP 5 exhibits the trigonal R3 space group. The 3,5-pdc ligand exhibits eight diverse coordination modes in CPs 1-6, whereas the adipic acid spacer in CP 6 shows only one coordination mode (μ4-κO:κO,O:κO:κO,O). The organic ligands interconnect with metal ions to generate 3D metal-organic frameworks with a variety of intriguing topologies. Theoretical studies, DFT calculations and Hirshfeld surface analysis support the structures adopted by the various CPs. CPs 3 (Sm) and 4 (Eu) emit strong ligand-sensitized characteristic f-f luminescence. Weak ferromagnetic interactions have been studied at low temperatures for CP 1 and CP 5.

Conversion of lanthanide glutarate chlorides with interstitial THF into lanthanide glutarates with unprecedented topologies

Abstract Using slow diffusion methods at room temperature (RT), we obtained four isomorphous lanthanide glutarate chlorides, accommodating interstitial THF and water molecules, [Ln2(Glut)2Cl2(H2O)8]·2H2O·THF (1–4), with Ln = La (1), Ce (2), Pr (3), Nd (4). They assemble as 3-dimensional (3D) lanthanide (Ln) coordination polymers with LnO10 coordination polyhedra. Their topology was elucidated to be a 4-coordinated sql net. 1–4 slowly dissolve in water liberating the entrapped THF molecules and reassemble as regular Ln-glutarate hydrates when the solution is deprived of THF and water by slow evaporation. The new products crystallize as [Ln2(Glut)3(H2O)3]·5H2O (5–7), with Ln = La (5), Ce (6), Pr (7), and [Nd2(Glut)3(H2O)2]·3.5H2O (8). 5–7 are isomorphous and crystallize as 3D-networks with two crystallographically independent LnO10 and LnO9 coordination spheres that assemble into Ln2O18 and Ln2O16 polyhedra via edge sharing. Their topology has not previously been observed and was found to be a 3,4,4,5,6-coordinated 3,4,4,5,6T61 net. The known compound 8 crystallizes also as a 3D-network and is isomorphous to other previously described lanthanide glutarate hydrates. 8 has a 3,4,5-coordinated 3,4,5T202 net topology, which has not been determined before.

White Light Emitting EuIII and TbIII Doped Lanthanide Coordination Polymers Based on in Situ Formed Nitrilotriacetic Anion

Three 2D lanthanide coordination polymers of in situ formed nitrilotriacetic anion (NTA3−) have been hydrothermally synthesized with N-(2-carbamoylmethyl) iminodiacetic acid (H2ADA) as starting material. The photoluminescence properties as well as the energy-transfer behavior of the resulted coordination polymers are studied in detail and the investigations reveal that both EuIII and TbIII complexes show intense emissions characteristic of EuIII and TbIII ion under irradiation of 399 nm. Considering the blue-emission of compound GdIII and the intense emission of EuIII and TbIII compounds, we afforded EuIII and TbIII doped white light emitting materials by the different combination of the doped EuIII and TbIII concentrations.

Structure Variation from One-Dimensional Chain to Three-Dimensional Architecture: Effect of Ligand on Construction of Lanthanide Coordination Polymers

Four lanthanide coordination polymers were constructed from mixed ligands of phenanthroline derivative and flexible polydentate ligands, [Gd2(1,3-BDC)3(MOPIP)2]n⋅nH2O (1), [Gd(1,4-BDC)1.5(MOPIP)]n (2), [Yb(1,4-BDC)1.5(MOPIP)]n (3) and [Sm(1,4-BDC)1.5(MOPIP)]n (4), (MOPIP = 2-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, 1,3-BDC = benzene-1,3- dicarboxylic acid, 1,4-BDC = benzene-1,4-dicarboxylic acid). The polymers have been synthesized under hydrothermal conditions and structurally characterized by single crystal X-ray diffraction analysis. Compound 1 possesses one-dimensional chain structure, and expands into the three-dimensional supramolecular architecture by π⋯π stacking and hydrogen-bonding interactions. Meanwhile, compounds 2–4 exhibit three-dimensional frameworks with pcu topology (4 12⋅6 3). The structural differences among such compounds show that the steric hindrances of benzene dicarboxylic acid ligands play a key role in the assembly and the structures of the title compounds. Compounds 1 and 2 act as efficient Lewis acid catalysts for the cyanosilylation of benzaldehyde in high yields, due to the strong Lewis acidity. A series of four 3-dimensional (3D) lanthanide coordination polymers were prepared which exhibit different structures and excellent catalytic activity in the cyanosilylation of benzaldehyde.

Lanthanide contraction effect on the crystal structures of 2D lanthanide coordination polymers based on 2-(trifluoromethyl)-1H-imidazole-4,5-dicarboxylic acid

A series of new two-dimensional (2D) lanthanide(III) coordination polymers, namely {[Ln2(μ 2-HTFMIDC)3(DMA)4] · 2H2O} n [Ln = Pr (1); Nd (2); Sm (3); Eu (4); H3TFMIDC = 2-(trifluoromethyl)-1H-imidazole-4,5-dicarboxylic acid, DMA = N,N′-dimethylacetamide] for type I and {[Ln2(μ 2-HTFMIDC)3(DMA)2(H2O)2] · DMA} n [Ln = Eu (5); Gd (6)] for type II, have been successfully prepared under solvothermal conditions and structurally characterized for the first time. Both two types of structures exhibit similar 2D honeycomb-like networks, which are constructed by the linkages of μ 2-HTFMIDC2− bis-(bidentate) bridging ligands and Ln(III) metal centers. However, slightly different ABAB stacking fashions of the 2D layers and distinctly different hydrogen bonding interactions between the neighboring 2D layers are observed in crystal structures of type I and type II, which may be attributed to the lanthanide contraction effect. Meanwhile, the solid-state luminescent properties of 4 and 5 have been also investigated.

Hybrid materials based on novel 2D lanthanide coordination polymers covalently bonded to amine-modified SBA-15 and MCM-41: assembly, characterization, structural features, thermal and luminescence properties.

Three novel 2D coordination polymers [Tb2(μ4-L)2(μ-HL)(μ-HCOO)(DEF)]n (Tb-L), [Eu(μ4-L)(L)(H2O)2]n (Eu-L), and [Nd(μ4-L)(L)(H2O)2]n (Nd-L) were assembled from the corresponding lanthanide(iii) nitrates and 5 methoxy-(4-benzaldehyde)-1,3-benzenedicarboxylic acid (H2L) as a main multifunctional building block bearing carboxylate and aldehyde functional groups, using H2O/DEF {DEF = N,N-diethylformamide} as a reaction medium. The obtained coordination polymers were isolated as stable microcrystalline solids and fully characterized by elemental analysis, FT-IR spectroscopy, TGA, BET, PXRD, and single-crystal X-ray diffraction methods. Their structures feature intricate 2D metal-organic networks, which were topologically classified as underlying layers with the 4,6L26 (for Tb-L) or sql (for Eu-L and Nd-L) topologies. Besides, a novel series of mesoporous hybrid materials wherein the Tb-L, Eu-L, or Nd-L coordination polymers are covalently grafted into the amine-functionalized SBA-15-NH2 or MCM-41-NH2 matrices (via the formation of Schiff-base groups) was also synthesized and fully characterized. These hybrid materials show high thermal and photoluminescence stability, as well as remarkable chemical resistance to boiling water, and acidic or alkaline medium. Luminescent properties of the parent coordination polymers and derived hybrid materials are investigated in detail, showing that the latter combine the luminescent characteristics (intense green or red emissions and excellent stability) of lanthanide coordination polymers and structural features of ordered mesoporous silica molecular sieves. Moreover, light emitting devices were assembled, by coating the hybrid materials onto the surface of UV-LED bulbs, and showed excellent light emitting properties.

From 1D to 3D lanthanide coordination polymers constructed with pyridine-3,5-dicarboxylic acid: synthesis, crystal structures, and catalytic properties

Three series of lanthanide coordination polymers have been synthesized. The structural difference may be derived from the lanthanide contraction. Moreover, we also discussed the size-selective catalytic activity towards cyanosilylation of aldehydes.

Three unprecedented high-connected 3D lanthanide–organic frameworks based on benzene-1,2,4,5-tetracarboxylic acid

Three unprecedented high-connected 3D lanthanide coordination polymers based on benzene-1,2,4,5-tetracarboxylic acid (H4bta), {[Ln2(bta)1.5(H2O)4]·3H2O}n (Ln=La (1) and Ce (2)) and [Pr(bta)0.5(H2bta)0.5(H2O)]n (3), have been synthesized under hydrothermal conditions. Complexes 1 and 2 show trinodal (4,4,10)-connected 3D network structures consisting of tetranuclear metal clusters bridged by bta4− ligands, and a chair conformation hexamer water cluster can be found within the cage enclosed by eight neighboring tetranuclear metal clusters in the two complexes. While 3 consists of 2D {Pr(bta)0.5}n layers linked by H2bta2− ligands, resulting in an unprecedented trinodal (4,6,10)-connected 3D topological network. The organic ligand exhibits five kinds of coordination modes, in which one of them is reported for the first time. Moreover, the luminescent properties of 1–3 have also been investigated.