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A pH-stable and solvent-stable Eu3+-based MOF can selectively and sensitively recognize Cr3+/Al3+/Ga3+via obvious turn-on and blue-shift fluorescence. More interestingly, the fluorescence test papers and LED lamps have been successfully developed.

A water-stable and pH-stable CP-based fluorescence probe (JXUST-27) can sense SA via fluorescence quenching with high selectivity and sensitivity. Remarkably, the fluorescence film and LED lamp have been further developed to detect SA.

A water and pH stable CdII-based MOF can be used as a good sensor for Hg2+ ions in aqueous solution. Intriguingly, LED lamps, test papers and luminescent films have been successfully developed to simply detect Hg2+ ions.

A stable CdII-based MOF with a narrow band gap could selectively and sensitively recognize l-histidine via obvious turn-on and fluorescence blue-shift effects. More interestingly, LED lamps of JXUST-14 and JXUST-14@His were developed successfully.

The water and pH stabilities of JXUST-12 have been greatly improved by SCSC transformation and JXUST-12a exhibits high selectivity and sensitivity toward drug.

A new ZnII-based coordination polymer could selectively and sensitively recognize NFT and DCN via turn-off effect. Interestingly, a mixed matrix film for visualizable sensing has been successfully developed.

A ZnII-based coordination polymer was synthesized by a mixed-ligand strategy, and it could be viewed as the first bifunctional fluorescent sensor with good stability for acac and l-His via a fluorescence red shift and enhancement.

A novel ZnII-based metal-organic framework with the formula of {[Zn2(BBIP)2(NDC)2]·H2O}n (JXUST-5) derived from 3,5-bis(benzimidazol-1-yl)pyridine (BBIP) and 1,4-naphthalenedicarboxylic acid (H2NDC) has been synthesized. The adjacent ZnII ions are linked through two BBIP ligands to form a [Zn2(BBIP)2] secondary building unit (SBU). The neighbouring SBUs are further connected by NDC2− with μ2-η1:η1 and μ2-η1:η1:η1 bridging modes to form a two-dimensional (2D) framework. Topological analysis shows that JXUST-5 could be simplified as an uninodal fes topology with a point symbol of {4.82}. Furthermore, the 2D framework net could be extended through C-H···π interaction to form the three-dimensional supramolecular structure. Luminescent experiments suggest that JXUST-5 could selectively and sensitively recognize Al3+ and Ga3+ through fluorescence enhancement effect along with a relatively large red shift. The detection limits for Al3+ and Ga3+ are 0.17 and 0.69 ppm, respectively. Interestingly, the sensing process for both Al3+ and Ga3+ could be directly observed with naked eyes under 365 nm UV lamp. Notably, JXUST-5 could be recycled at least five times as a fluorescent sensor toward Al3+ and Ga3+, which is the second example of turn-on MOF based fluorescent sensor toward Ga3+.

A stable benzothiadiazole-based Eu(iii) metal–organic framework with cco topology has been successfully constructed, and represents the multifunctional fluorescence sensor toward Fe3+, MnO4− and Cr2O72− in aqueous solutions.

A dual-functional sensor based on a two-dimensional metal–organic framework (MOF), namely, {[Cd(BBZB)(2,6-NDC)]·CH3OH}n (JXUST-6, BBZB = 4,7-bis(1H-benzimidazole-1-yl)-2,1,3-benzothiadiazole and 2,...

A novel water-stable Cd

A new benzothiadiazole-based MOF {[Zn(BIBT)(oba)]·DMA}n (JXUST-3, BIBT = 4,7-bi(1H-imidazol-1-yl)benzo-[2,1,3]thiadiazole and H2oba = 4,4′-oxybisbenzoate) has been solvothermally synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy and TGA. The fluorescence studies suggest that JXUST-3 could simultaneously selectively sense trivalent metal ions including Al3+, Cr3+ and Fe3+ by a turn-off effect, and the detection limits are 0.055, 0.049 and 0.056 μM, respectively. Moreover, JXUST-3 exhibits relatively good thermal and chemical stabilities and reusability. The fluorescent test paper also displayed an obvious turn-off effect, indicating that JXUST-3 can be used as a potential multi-response fluorescent probe. The possible quenching mechanisms of JXUST-3 for Al3+ and Fe3+ were competitive energy absorption, and for Cr3+ ions, they were competitive energy absorption and weak interactions between Cr3+ and the framework. Therefore, JXUST-3 could be viewed as a transition metal MOF fluorescence sensor for Al3+, Cr3+ and Fe3+ by the turn-off effect, simultaneously.

A novel Zn2+-based metal-organic framework (MOF) with the formula of {[Zn(μ2-η1:η1-BBIP)(μ2-η1:η1:η1-OBA)]•3H2O}n, denoted as JXUST-7, has been successfully assembled by the choice of semi-rigid N-donor 3,5-bis(benzimidazol-1-yl)pyridine (BBIP) and flexible 4,4′-oxybisbenzoate (H2OBA). The adjacent Zn2+ ions are linked through OBA2- ligand with μ2-η1:η1:η1 bridging mode to form an infinite one-dimensional (1D) Zn2+-OBA2- chain. The neighbouring 1D chains are further connected by BBIP ligand with μ2-η1:η1 bridging mode to gain a two-dimensional (2D) sheet layer structure. Topological analysis indicates that the whole 2D structure of JXUST-7 could be simplified as a uninodal sql topology with a point symbol of {44.62}. Furthermore, the opposite parallel 2D layers are further packed by face-to-face π-π interaction to generate a three-dimensional supramolecular structure. Luminescent experiments reveal that JXUST-7 could be considered as a multi-responsive MOF-based fluorescent probe toward Fe3+, Cr2O72- and acetylacetone (acac) via the fluorescence quenching (turn-off) effect. The detection limits for Fe3+, Cr2O72- and acac are 0.14, 1.33 and 6.53 ppm, respectively. The fluorescence quenching mechanism was analyzed in detail by powder X-ray diffraction, fluorescence lifetime measurement, XPS, theoretical calculation and UV-Vis absorption spectra. More importantly, JXUST-7 could be cyclically utilized at least five times for detecting Fe3+, Cr2O72- and acac.

A novel luminescent CdII-based metal–organic framework {[Cd(BBIP)(TBIP)]·EtOH}n (1) derived from the multidentate 5-tert-butylisophthalic acid (H2TBIP) and the semi-rigid N-donor 3,5-bis(benzimidazol-1-yl)pyridine (BBIP) has been solvothermally synthesized and structurally characterized by using infrared spectroscopy, thermal analysis, single-crystal X-ray diffraction and powder X-ray diffraction. The adjacent CdII ions are linked by two carboxylate groups of one TBIP2− ligand with chelating mode to form a one-dimensional CdII-TBIP2− chain, which is further connected by the BBIP ligand to obtain a two-dimensional network. Interestingly, the fluorescence experiments indicate that 1 could be considered as a good multi-responsive sensing material for detecting Fe3+, MnO4−, Cr2O72−, salicylaldehyde (SA) and ethylenediamine (EDA) via the turn-off effect, with the detection limits of 0.53, 0.98, 3.6, 0.42 and 5.3 ppm, respectively. The luminescence quenching effect induced by Fe3+ could be mainly ascribed to the competitive absorption mechanism. The electron-transfer transition and competitive absorption mechanism could be used to explain the luminescence quenching of MnO4− and Cr2O72−. The turn-off effect of 1 on SA could be ascribed to the photoinduced electron-transfer and competitive absorption mechanisms. Meanwhile, the possible mechanism of fluorescence quenching caused by EDA could be attributed to the structure collapse. More importantly, 1 could be regenerated and reused after five cycles for Fe3+, MnO4−, Cr2O72− and SA detection. In a nutshell, 1 could be employed as a multi-responsive luminescent sensor used for the highly selective and sensitive detection of metal ions, anions and small organic molecules.

A three-dimensional metal–organic framework, namely {[Zn3(BIBT)(BTC)5/3(μ3-OH)]·solvents}n (JXUST-4), has been synthesized by using ZnII ions, and BIBT and H3BTC ligands (BIBT = 4,7-bi(1H-imidazol-1-yl)benzo-[2,1,3]thiadiazole and H3BTC = 1,3,5-benzenetricarboxylic acid). JXUST-4 shows a new (3,3,7)-connected topology net containing a trinuclear ZnII cluster, uncoordinated N atoms of BIBT and uncoordinated carboxylate O atoms of H3BTC, which facilitates the interaction between the framework and analytes. Fluorescence studies indicate that JXUST-4 generates light yellow luminescence, which could be ascribed to ligand-centered emission. More importantly, JXUST-4 could be viewed as an effective fluorescent sensor toward acetylacetone through an obvious fluorescence red-shift with high sensitivity, efficient selectivity, and outstanding recycling capacity. Furthermore, the possible sensing mechanism of JXUST-4 toward acetylacetone is due to electron transfer and weak interactions between the analyte and framework.

A novel Cd

Enhancer of zeste homolog 2 (EZH2) was recently found to play an important role in cardiovascular disease. However, the role of EZH2 in vascular remodeling induced by mechanical stretch is poorly understood. The aim of the present work was to investigate the role of EZH2 in regulating smooth muscle cell function through mechanical stretch assays and to explore the underlying mechanisms.WT C57BL/6 J mice underwent sham surgery or abdominal aortic constriction. The level of EZH2 expression was determined by Western blotting and immunohistochemical staining. We demonstrated the thickness of vascular remodeling by HE staining. JASPAR was used to predict transcription factors that could affect EZH2. Chromatin immunoprecipitation was used to substantiate the DNAprotein interactions. Promoter luciferase assays were performed to demonstrate the activity of the transcription factors.We found that in vivo, AAC significantly reduced EZH2 protein levels in the thoracic aorta. Smooth muscle-specific overexpression of EZH2 was sufficient to attenuate the AAC-induced reduction in trimethylation of Lys-27 in histone 3 and thickening of the arterial media. Administration of GSK-J4 (an inhibitor of H3K27me3 demethylase) induced the same effects. In addition, we found that mechanical stretch regulated the expression of EZH2 through the Yes-associated protein (YAP)- transcriptional factor TEA domain 1 (TEAD) pathway. TEAD1 bound directly to the promoter of EZH2, and blocking the YAP-TEAD1 interaction inhibited EZH2 downregulation due to mechanical stretch.This study reveals that mechanical stretch downregulates EZH2 through the YAP-TEAD1 pathway, thereby aggravating smooth muscle cell apoptosis and vascular remodeling.

A novel Co-based metal–organic framework (MOF) with the formula of {[Co3(BIBT)3(BTC)2(H2O)2]·solvents}n (JXUST-2, where JXUST denotes Jiangxi University of Science and Technology, BIBT = 4,7-bi(1H-...

Vascular calcification (VC) is a significant risk factor for cardiovascular mortality and morbidity in patients with atherosclerosis (AS), chronic kidney disease, and diabetes. Dickkopf1 (Dkk1) is a multifunctional secreted glycoprotein that has been explored as a novel potential antitumor target. Recently, Dkk1 was shown to be closely associated with AS development. However, the role of Dkk1 in VC remains elusive. In this study, we explored the role and molecular mechanisms of Dkk1 in VC based on a smooth muscle-specific Dkk1-knockout (Dkk1

A new metal-organic framework (MOF) {[Cd2 (bbib)2 (ndc)2 ]⋅2DMF}n (JXUST-1) (bbib=1,3-bis(benzimidazolyl)benzene, H2 ndc=1,4-naphthalenedicarboxylic acid, DMF=N,N-dimethylformamide) has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, PXRD, TGA, IR and elemental analysis. JXUST-1 exhibits a three-dimensional 6-connected pcu topology with a Schlafli symbol {412 .63 } constructed by [Cd2 (CO2 )3 ] secondary building units. Fluorescence studies show that this MOF can sensitively and selectively recognize Al3+ via a fluorescence enhancement effect, and the detection limit is 0.048 ppm. Furthermore, JXUST-1 displays relatively good thermal and chemical stabilities as well as reusability. All these results suggest JXUST-1 to be a highly selective and recyclable luminescent sensing material for the detection of Al3+ .

A ZnII-based metal-organic framework (MOF) with a rare tcj topology has been solvothermally synthesized and displays relatively good thermal and chemical stabilities. Interestingly, the MOF can sensitively and selectively sense acetylacetone (acac) via a fluorescence enhancement effect with a detection limit of 0.10 ppm and good reusability, which demonstrates the first example of a MOF-based turn-on fluorescent sensor for acac.

An approximate model can be used to replace the real model to reduce the computing time and guarantee the feasibility of optimization. However, the approximate model must meet the required accuracy. The higher the accuracy of the approximate model, the higher the reliability of optimization results. In this study, a finite element model for the 40% offset impact of minibus was established, with the thickness of 10 plates in the front of the car body as the design variable and peak acceleration of B pillar lower end, the total mass, and the intrusion volume of dashboard beam, steering column hole, and clutch pedal as the response values. We obtained 70 sample points by the Latin hypercube experimental design method and built approximate models of design variables and the response. Then, we compared the relative error scatter, mean relative error, and decision coefficient of the response surface approximate model, radial basis function network approximate model, kriging approximate model, and orthogonal polynomial approximate model. Results show that the prediction accuracy of the response surface approximate model and radial basis function network approximate model in the peak acceleration of B pillar lower end and the intrusion volume of the steering column hole and clutch pedal does not meet the requirement. The orthogonal polynomial approximate model has a high prediction accuracy in total mass, but its prediction accuracy in other responses does not meet the requirement. In addition, all three approximate models are obviously influenced by the linear relationship between the response and the variables. The kriging approximate model meets the required prediction accuracy of the four responses and is less affected by the linear relationship. Thus, the kriging approximate model is suitable to replace the original model. Then, particle swarm optimization can be performed to optimize the kriging approximate model. This study shows that the kriging approximate model has high fitting precision, and the optimization results reach the expected aim.

Two new GdIII complexes with the formulas of [Gd(ma)2(H2O)2]·2H2O (1) and {[Gd(ma)(ox)0.5(H2O)]·2H2O}n (2) (H2ma = DL-malic acid and H2ox = oxalic acid) have been successfully prepared by using Gd2O3 or Gd(NO3)3 as metal ion sources. Complex 1 exhibits a discrete mononuclear structure, while complex 2 displays a three-dimensional ‘layer-pillar’ structure with ox2− anions as pillars that are generated in situ. Magnetic studies suggest the presence of ferromagnetic couplings between the intramolecular or interlayer GdIII ions and large magnetocaloric effects with −ΔSmaxm = 32.1 J kg−1 K−1 (1) and 44.6 J kg−1 K−1 (2) for ΔH = 7 T. Therefore, they are good candidates as magnetic refrigerants.

Three zinc(II) metal-organic frameworks have been solvothermally synthesized with V-shaped 1,3-bis(1-imidazolyl)benzene (bib) and 4,4'-oxydibenzoic acid (4,4'-H2oba), namely {[Zn(bib)(oba)]⋅solvents}n (1), {[Zn(bib)(oba)]·2H2O}n (2) and {[Zn2(bib)2(oba)2]⋅2EtOH⋅H2O}n (3). All of them are characterized by single-crystal X-ray diffraction, infrared spectra and powder X-ray diffraction. Complex 1 presents a two-fold interpenetrating three-dimensional structure with 4-connected (65.8) topology. While, complexes 2 and 3 exhibit double layer cavity and double chains based two-dimensional structure, respectively. Luminescent studies indicate that 2 and 3 display selectively sensitive to electron-deficient nitroaromatic explosives with excellent anti-interference abilities.

A novel Co-based metal-organic framework (MOF) with the formula of {[Co

Two LnIII complexes derived from one aromatic monocarboxylate ligand, namely [Tb2(mnba)6(H2O)4]n (1) and [Dy2(mnba)4(μ3-OH)2(H2O)]n (2) (Hmnba = m-nitrobenzoic acid), have been prepared by similar synthetic procedures and structurally characterized. Complex 1 contains two identical one-dimensional (1D) chains with the syn,syn-carboxylate as linkers, while complex 2 takes the 1D chain structure with μ3--OH and carboxylate as bridge. Magnetic studies indicate that ferromagnetic interactions between intra-chain metal centers exist in 1 and 2 and only complex 2 exhibits field-induced slow magnetic relaxation behavior.

Six new coordination polymers (CPs) based on the V-shaped 1,3-bis(benzimidazolyl)benzene (bbib) have been synthesized under solvothermal conditions: [Zn(bbib)(ip)]n (1), {[Zn(bbib)(oba)]·solvents}n (2), {[Zn(bbib)(tp)]·DMF}n (3), [Cd(bbib)(ip)]n (4), {[Cd(bbib)(oba)]·H2O·solvents}n (5) and {[Cd(bbib)(tp)]·DMF}n (6) (ip = isophthalate, oba = 4,4′-oxybisbenzoate and tp = terephthalate). Complexes 1–3 display a plane minimal net, (4,4) sheet and a hexagonal plane net, respectively. The structures of 4–6 range from a 1D zigzag chain (4), 2D (4,4) sheet (5) to a 3D “pillar-layer” coordination framework with pcu α-Po topology (6). The structural transition from 1D to 3D among these complexes is realized with the aid of different auxiliary ligands. The results demonstrate that the conformations and coordination modes of dicarboxylate ligands make an impact on the structural diversity of ZnII/CdII coordination polymers. To the best of our knowledge, the CPs based on the bbib ligand have been successfully prepared for the first time. Moreover, complex 2 is a good bifunctional chemosensor for the detection of both Fe3+ and MnO4− with the detection limits of 3.31 ppm and 8.81 ppm, respectively, indicating that 2 could be used as an efficient fluorescent sensor with high sensitivity and selectivity for Fe3+ and MnO4−.

Two benzothiadiazole-based compounds, namely 4,7-di(1H-1,2,4-triazol-1-yl)benzo- [2] , [1] , [3] thiadiazole (1) and 4,7-di(1H-pyrazol-1-yl)benzo- [2] , [1] , [3] thiadiazole (2), have been constructed with Cu-catalyzed cross-coupling reactions. The fluorescence studies show that compound 1 has high selectivity and sensitivity toward TEA (triethylamine), EDA (ethylenediamine), TMEDA (N,N,N’,N’-tetramethylethylenediamine), MnO4− and ClO− by fluorescence quenching, and compound 2 also has high selectivity and sensitivity toward TEA and TMEDA via fluorescence quenching. The calculated detection limits of 1 for TEA, EDA, TMEDA, MnO4− and ClO− are 0.129, 0.635, 0.320, 9.820 and 12.740 μM, respectively. Meanwhile, the detection limits of compound 2 for TEA and TMEDA are 0.400 and 0.278 μM, respectively. Interestingly, compounds 1 and 2 are the first fluorescent sensors for the selective recognition of TMEDA.

Four transition metal–organic frameworks were solvothermally synthesized with V-shaped 1,3-bis(1-imidazolyl)benzene (bib) and two Y-shaped carboxylate ligands (1,3,5-benzenetricarboxylic acid (H3btc) and 3,5-pyridinedicarboxylic acid (H2pydc)), namely, {[M2(μ3-OH)(bib)(btc)]·H2O}n (M = Co (1) and Fe (2)) and {[M′2(μ3-OH)(μ2-NO3)(bib)(pydc)]·solvents}n (M′ = Co (3) and Ni (4)). All of them are characterized by single-crystal X-ray diffraction, infrared spectrosopy, and powder X-ray diffraction. Both complexes 1 and 2 present two-dimensional (3,8)-connected layer structures, and the point symbol is (3.42)2(34.46.56.68.73.8), but Fe2 in 2 is weakly coordinated to O5 as a trigonal bipyramidal geometry compared with the tetrahedral Co2 in 1, while complexes 3 and 4 exhibit three-dimensional “pillar-layer” structures with (3,8)-connected tfz-d net. Interestingly, nitrate anions with a rare μ2-η2 coordination mode take part in coordination, and rectangular channels along the c axis exist in 3 and 4. Magnetic stu...

Two di- and trinuclear Gd(III) clusters with the formulas {[Gd2(omba)6(phen)2]·2H2O} (1) and [Gd3(Hsa)5(sa)2(phen)3] (2) (Homba = o-methoxybenzoic acid, H2sa = salicylic acid and phen = 1,10-phenanthroline) have been prepared through the hydrothermal reactions. Complex 1 takes a dinuclear structure and two Gd(III) are bridged by two syn-syn-μ2-η1:η1 and two syn-syn-μ2-η1:η2 carboxylates. While complex 2 is a trinuclear cluster linked by one syn-syn-μ2-η1:η2 and two syn-syn-μ2-η1:η1 carboxylates. Magnetic studies reveal the key impact of magnetic density on the magnetocaloric effect in Gd(III) systems. They exhibit relatively weak magnetic interactions and significant magnetic entropy changes with −ΔSmmax = 17.1 J kg−1 K−1 and 22.5 J kg−1 K−1 (T = 2 K, ΔH = 7 T), respectively.

By using Gd2O3, propanedioic acid (H2pda) and oxalic acid (H2ox), a new Gd-based metal–organic framework (MOF) [Gd(pda)(ox)0.5(H2O)2]n (1) has been successfully constructed and structurally characterized. Interestingly, temperature- and vapor-induced reversible single-crystal-to-single-crystal transformations occurred and two new MOFs, namely [Gd(pda)(ox)0.5(H2O)]n (1a) and [Gd(pda)(ox)0.5]n (1b), have been obtained. Complex 1 displays a two-dimensional (2D) layer structure composed of zigzag [Gd(pda)]n chains and it could also be made up of numerous Gd6 macrocycles. Thermal dehydration leads to more complicated three-dimensional (3D) ‘pillar-layer’ structures (1a and 1b) with the same coordination mode of pda2− anions. Magnetic studies suggest the presence of ferromagnetic couplings between the intrachain or intralayer GdIII ions and large magnetocaloric effects (MCEs) with −ΔSmaxm = 45.0 J kg−1 K−1 (1), 46.1 J kg−1 K−1 (1a) and 46.8 J kg−1 K−1 (1b) under a 7 T applied field. Therefore, the interest of ‘robust magnetocaloric MOFs’ is now extended to compounds showing weak ferromagnetic couplings and hence having better magnetocaloric performances for small field changes.

Three chain-based GdIII coordination polymers, namely [Gd2(SO4)3(phen)2(H2O)2]n (1), [Gd2(oda)2(ox)(H2O)6]n (2) and {[Gd2(glu)3(H2O)2]·4H2O}n (3) (phen = 1,10-phenanthroline, H2oda = oxydiacetic acid, H2ox = oxalic acid and H2glu = glutaric acid), have been successfully constructed by using multidentate O ligands under hydro/solvothermal conditions. Complex 1 has a one-dimensional (1D) chain bridged by inorganic sulfate, and complex 2 exhibits a 1D double-chain ladder-shaped structure connected by oxalate. While, complex 3 is a three-dimensional (3D) metal–organic framework composed of 1D chains. All of them display good thermal stabilities and large magnetic entropy changes with −ΔSmaxm > 31 J kg−1 K−1 (7 T), suggesting them to be good candidates for use as cryogenic magnetic refrigerants.

Isostructural CoII and MnII organic frameworks with anionic frameworks and counterions (Me2NH2)+, namely {[M2Cl2(BTC)4/3]·(Me2NH2)+2·4/3H2O}n (M = Co (1) and Mn (2)), have been constructed by one-pot synthesis. Complexes 1 and 2 take paddle-wheel-like dinuclear metal cluster-based three-dimensional structures. Thermogravimetric analysis and variable-temperature powder X-ray diffraction spectra suggested that 1 displays better thermal stability than 2. Both exhibit relatively high proton conductivities at 65% relative humidity (RH) and room temperature (σ > 2.5 × 10–4 S cm–1); however, complex 1 possesses the better cycling capability and stability with Ea = 0.21 eV under 65% RH.

A new metal-organic framework (MOF) {[Cd

A Zn

Two dinuclear GdIII cluster complexes with the formulas [Gd2(iba)6(bipy)2] (1) and [Gd2(nic)6(H2O)4] (2) (Hiba = isobutyric acid, Hnic = nicotinic acid and bipy = 2,2´-bipyridine) have been constructed by using gadolinium oxide as GdIII ion source under hydrothermal conditions. Although both 1 and 2 exhibit dinuclear structures, the coordination fashions are totally different. In 1, the carboxylate groups of Hiba take syn-syn-μ2-η1:η1, syn-syn-μ2-η1:η2 and syn-μ-η1:η1 modes and bipy acts as the chelating ligand. While the carboxylate groups of Hnic display syn-syn-μ2-η1:η1 and syn-μ-η1:η1 modes in 2 and two water molecules take part in coordination. Magnetic studies reveal weak ferromagnetic couplings and significant magnetic entropy changes with −ΔSmmax = 29.3 J kg−1 K−1 and 27.4 J kg−1 K−1 (ΔH = 7 T), respectively.

Two Gd2 cluster complexes with the formulas of [Gd2(dnba)6(phen)2] (1) and [Gd2(Hnsa)2(nsa)2(phen)2(H2O)2] (2) (Hdnba = 3,5-dinitrobenzoic acid, H2nsa = 5-nitrosalicylic acid and phen = 1,10-phenanthroline) respectively have been successfully synthesized under hydrothermal conditions. The GdIII ions of 1 are bridged by four carboxylates with syn-syn-μ2-η1:η1 and syn-syn-μ2-η1:η2 modes, while the GdIII ions of 2 are linked by two carboxylate ligands with only syn-syn-μ2-η1:η2 mode. Magnetic studies indicate that weak antiferromagnetic and ferromagnetic interactions exist between the adjacent GdIII ions within Gd2 clusters, respectively. Complexes 1 and 2 display distinct magnetocaloric effects induced by different magnetic interactions and magnetic densities. Notably, the maximum magnetic entropy changes (−ΔSmmax) of 1 and 2 reach 16.8 J kg−1 K−1 and 22.2 J kg−1 K−1 with ΔH = 7 T at 2 K and 3.5 K, respectively.

Two GdIII complexes, namely [Gd2(OH)2(oda)2(H2O)4]∞ (1) and {[Gd(fum)(ox)0.5(H2O)2]·2H2O}∞ (2) (H2oda = oxydiacetic acid, H2fum = fumaric acid and H2ox = oxalic acid), have been constructed via hydrothermal reactions. Complex 1 has a one-dimensional (1D) chain structure based on hydroxyl-bridged Gd2O2 cores, while complex 2 exhibits a three-dimensional (3D) framework consisting of Gd6 macrocycles, and can also be seen as a 3D layer-pillar structure with intersected channels occupied by guest water. Magnetic studies indicate that weak antiferromagnetic and ferromagnetic interactions exist between adjacent GdIII ions in 1 and 2, which display large magnetocaloric effects with −ΔSmaxm = 43.3 and 37.1 J kg−1 K−1 for ΔH = 7 T, respectively. Notably, the maximum entropy changes (−ΔSmaxm) of 1 and 2 reach 29.9 and 28.5 J kg−1 K−1, respectively, at 2 K for a moderate field change (ΔH = 3 T). Therefore, 1 and 2 could be regarded as potential magnetorefrigerants for low-temperature applications.