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The electrochemical splitting of water into hydrogen and oxygen is considered one of the most promising approaches to generate clean and sustainable energy. However, the low efficiency of the oxygen evolution reaction (OER) acts as a bottleneck in the water splitting process. Herein, interface engineering heterojunctions between ZIF‐67 and layered double hydroxide (LDH) are designed to enhance the catalytic activity of the OER and the stability of Co‐LDH. The interface is built by the oxygen (O) of Co‐LDH and nitrogen (N) of the 2‐methylimidazole ligand in ZIF‐67, which modulates the local electronic structure of the catalytic active site. Density functional theory calculations demonstrate that the interfacial interaction can enhance the strength of the Co—Oout bond in Co‐LDH, which makes it easier to break the H‐Oout bond and results in a lower free energy change in the potential‐determining step at the heterointerface in the OER process. Therefore, the Co‐LDH@ZIF‐67 exhibits superior OER activity with a low overpotential of 187 mV at a current density of 10 mA cm−2 and long‐term electrochemical stability for more than 50 h. This finding provides a design direction for improving the catalytic activity of OER., The interface of Co‐LDH@ZIF‐67 is built by the oxygen of cobalt layered double hydroxide (Co‐LDH) and nitrogen of the ZIF‐67, which can modulate the electronic structure of the catalytical site. The Co‐LDH@ZIF‐67 exhibits superior catalytical activity in oxygen evolution reaction with a low overpotential of 187 mV at a current density of 10 mA cm−2.

Covalent triazine frameworks (CTFs) with polypyridyl ligands are very promising supports to anchor photocatalytic complexes. Herein, we investigate the photophysical properties of a series of ligands which vary by the extent of the aromatic system, the nitrogen content and their topologies to aid in selecting interesting building blocks for CTFs. Interestingly, some linkers have a rotational degree of freedom, allowing both a trans and cis structure, where only the latter allows anchoring. Therefore, the influence of the dihedral angle on the UV‐Vis spectrum is studied. The photophysical properties are investigated by a combined computational and experimental study. Theoretically, both static and molecular dynamics simulations are performed to deduce ground‐ and excited state properties based on density functional theory (DFT) and time‐dependent DFT. The position of the main absorption peak shifts towards higher wavelengths for an increased size of the π‐system and a higher π‐electron deficiency. We found that the position of the main absorption peak among the different ligands studied in this work can amount to 271 nm; which has a significant impact on the photophysical properties of the ligands. This broad range of shifts allows modulation of the electronic structure by varying the ligands and may help in a rational design of efficient photocatalysts., The photophysical properties of various polypyridyl ligands have been investigated by a combined computational and experimental study in order to select interesting building blocks for covalent triazine frameworks. The position of the main absorption peak shifts towards higher wavelengths for an increased size of the π ‐system and a higher π ‐electron deficiency. The shift can amount to 271 nm among the different ligands; which has a significant impact on the photophysical properties.

Low-cost metal-free catalysts enable O2 activation as a key step in many important sustainable processes., Oxygen activation is a critical step in ubiquitous heterogeneous oxidative processes, most prominently in catalysis, electrolysis, and pharmaceutical applications. We present here our findings on metal-free O2 activation on covalent triazine frameworks (CTFs) as an important class of N-rich materials. The O2 activation process was studied for the formation of aldehydes, ketones and imines. A detailed mechanistic study of O2 activation and the role of nitrogen heteroatoms were comprehensively investigated. The electron paramagnetic resonance (EPR) and control experiments provide strong evidence for the reaction mechanism proving the applicability of the CTFs to activate oxygen into superoxide species. This report highlights the importance of a self-templating procedure to introduce N functionalities for the development of metal-free catalytic materials. The presented findings reveal an important step toward the use of CTFs as inexpensive and high-performance alternatives to metal-based materials not only for catalysis but also for biorelated applications dealing with O2 activation.

Earth-abundant transition metal (Fe, Co, or Ni) and nitrogen doped porous carbon electrocatalysts (M-N-C, where M denotes the metal) were synthesized from cheap precursors via silica-templated pyrolysis. The effect of the material composition and structure (i.e., porosity, nitrogen doping, metal identity, and oxygen functionalization) on the activity for the electrochemical CO2 reduction reaction (CO2RR) was investigated. The metal-free N-C exhibits a high selectivity but low activity for CO2RR Incorporation of the Fe and Ni, but not CO2 sites in the N-C material is able to significantly enhance the activity. The general selectivity order for CO2-to-CO conversion in water is found to be Ni > Fe >> Co with respect to the metal in M-N-C, while the activity follows Ni, Fe >> Co. Notably, the Ni-doped carbon exhibits a high selectivity with a faradaic efficiency of 93% for CO production. Tafel analysis shows a change of the rate-determining step as the metal overtakes the role of the nitrogen as the most active site. Recording the X-ray photoelectron spectra and extended X-ray absorption fine structure demonstrates that the metals are atomically dispersed in the carbon matrix, most likely coordinated to four nitrogen atoms and with carbon atoms serving as a second coordination shell. Presumably, the carbon atoms in the second coordination shell of the metal sites in M-N-C significantly affect the CO2RR activity because the opposite reactivity order is found for carbon supported metal meso-tetraphenylporphyrin complexes. From a better understanding of the relationship between the CO2RR activity and the material structure, it becomes possible to rationally design high-performance porous carbon electrocatalysts involving earth-abundant metals for CO2 valorization.

Aza-boron-dipyromethene (aza-BODIPY) derivative 4 (-Dipyrrinyl aza-BODIPY) was prepared readily from -formyl aza-BODIPY and used as a key synthon for the preparation of aza-BODIPY-metal dipyrrinyl conjugates. Three aza-BODIPY-metal dipyrrinyl conjugates (M=Re(I), Ni(II) and Zn(II)) were prepared by treating -dipyrrinyl aza-BODIPY with appropriate metal salts at reflux temperature followed by column chromatographic purification. The aza-BODIPY-metal dipyrrinyl conjugates were freely soluble in common organic solvents and stable in solid and in solution states. The conjugates were characterized in detail by HR-MS, 1D & 2DNMR, absorption, electrochemical and fluorescence techniques and the structure of the one of the conjugate was deduced by X-ray crystallography. The X-ray structure revealed that 1,3,5,7-tetratolyl aza-BODIPY and Re(I) dipyrrinyl moieties in aza-BODIPY-Re(I) dipyrrinyl conjugate were perpendicular to each other with a dihedral angle of 89 degrees. The absorption and electrochemical studies revealed that the aza-BODIPY and dipyrrinyl moieties in conjugates interact weakly and retain their individual properties. The aza-BODIPY-metal dipyrrinyl conjugates were very weakly fluorescent.

The archetypal silica- and aluminosilicate-based zeolite-type materials are renowned for wide-ranging applications in heterogeneous catalysis, gas-separation and ion-exchange. Their compositional space can be expanded to include nanoporous metal chalcogenides, exemplified by germanium and tin sulfides and selenides. By comparison with the properties of bulk metal dichalcogenides and their 2D derivatives, these open-framework analogues may be viewed as three-dimensional semiconductors filled with nanometer voids. Applications exist in a range of molecule size and shape discriminating devices. However, what is the electronic structure of nanoporous metal chalcogenides? Herein, materials modeling is used to describe the properties of a homologous series of nanoporous metal chalcogenides denoted np-MX2, where M = Si, Ge, Sn, Pb, and X = O, S, Se, Te, with Sodalite, LTA and aluminum chromium phosphate-1 structure types. Depending on the choice of metal and anion their properties can be tuned from insulators to semiconductors to metals with additional modification achieved through doping, solid solutions, and inclusion (with fullerene, quantum dots, and hole transport materials). These systems form the basis of a new branch of semiconductor nanochemistry in three dimensions.

The ability of 3-(diphenylphosphinomethyl)-benzene-1,2-dithiol (pbdtH(2)) to act as ditopic ligand was probed in reactions with selected group-10-metal complexes. Reactions with [(cod)PdCl2] afforded a mixture of products identified as [Pd(pbdtH)(2)], [Pd-2(mu(2)-pbdt)(2)] and [Pd-3(mu(2)-pbdt)(2)Cl-2]. The polynuclear complexes could be isolated after suitably adjusting the reaction conditions, and heating of a mixture in a microwave reactor effected partial conversion into a further complex [Pd-3(mu(2)-pbdt)(3)]. Reaction of pbdtH(2) with [Ni(H2O)(6)Cl-2] gave rise to a complex [Ni-2(mu(2)-pbdt)(2)], which was shown to undergo two reversible 1e(-)-reduction steps. Reaction of [Pd(pbdtH)(2)] with [Au(PPh3)Cl] afforded heterotrinuclear [PdAu2(mu(2)-pbdt)(2)(PPh3)]. All complexes were characterized by analytical, spectroscopic and single-crystal X-ray diffraction studies. Their molecular structures confirm the ability of the pbdt(2-) unit to support simultaneous P,S- and S,S-chelating coordination to two metal centers.

MAF-252, a non-porous crystalline coordination polymer, is obtained from the solvent-free reaction of ZnO with 3-(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole. MAF-252 can be synthesized in powder form and deposited as thin films, starting from ZnO powder and layers, respectively. Chemical vapour deposition (CVD) of MAF-252 enables conformal and patterned thin films, even on high aspect ratio features. ispartof: European Journal Of Inorganic Chemistry vol:2020 issue:1 pages:71-74 status: Published online

Electrochemical water splitting has attracted significant attention as a key pathway for the development of renewable energy systems. Fabricating efficient electrocatalysts for these processes is intensely desired to reduce their overpotentials and facilitate practical applications. Recently, metal-organic framework (MOF) nanoarchitectures featuring ultrahigh surface areas, tunable nanostructures, and excellent porosities have emerged as promising materials for the development of highly active catalysts for electrochemical water splitting. Herein, the most pivotal advances in recent research on engineering MOF nanoarchitectures for efficient electrochemical water splitting are presented. First, the design of catalytic centers for MOF-based/derived electrocatalysts is summarized and compared from the aspects of chemical composition optimization and structural functionalization at the atomic and molecular levels. Subsequently, the fast-growing breakthroughs in catalytic activities, identification of highly active sites, and fundamental mechanisms are thoroughly discussed. Finally, a comprehensive commentary on the current primary challenges and future perspectives in water splitting and its commercialization for hydrogen production is provided. Hereby, new insights into the synthetic principles and electrocatalysis for designing MOF nanoarchitectures for the practical utilization of water splitting are offered, thus further promoting their future prosperity for a wide range of applications.

International audience; Treatment of MOF-5 with NbCl4(THF) 2 in acetonitrile leads to incorporation of Nb(IV) centers in a fashion that diverges from the established cation metathesis reactivity of this iconic material. A combination of X-ray absorption spectroscopy analysis and reactivity studies altogether supported by density functional theory computational studies document an unprecedented binding mode for the Zn4O(O2C-) 6 secondary building units (SBUs), which in Nb(IV)-MOF-5 function as k 2-chelating ligands for NbCl4 moieties, with no exchange of Zn2+ observed. This unusual reactivity expands the portfolio of postsynthetic modification techniques available for MOFs, exemplified here by MOF-5, and underscores the diverse coordination environments offered by this and potentially other MOFs towards heterometal species.

In a comparative study of the electrocatalytic CO2 reduction, cobalt meso-tetraphenylporphyrin (CoTPP) is used as a model molecular catalyst under both homogeneous and heterogeneous conditions. In the former case, employing N,N-dimethylformamide as solvent, CoTPP performs poorly as an electrocatalyst giving low product selectivity in a slow reaction at a high overpotential. However, upon straightforward immobilization of CoTPP onto carbon nanotubes, a remarkable enhancement of the electrocatalytic abilities is seen with CO2 becoming selectively reduced to CO (>90%) at a low overpotential in aqueous medium. This effect is ascribed to the particular environment created by the aqueous medium at the catalytic site of the immobilized catalyst that facilitates the adsorption and further reaction of CO2. This work highlights the significance of assessing an immobilized molecular catalyst from more than homogeneous measurements alone.

Properties of four polymers of intrinsic microporosity containing Trager's base units were assessed for CO2 capture experimentally and computationally. Structural properties included average pore size, pore size distribution, surface area, and accessible pore volume, whereas thermodynamic properties focused on density, CO2 sorption isotherms, and enthalpies of adsorption. It was found that the shape of the contortion site plays a more important role than the polymer density when assessing the capacity of the material, and that the presence of a Trager base unit only slightly affects the amount adsorbed at low pressures, but it does not have any significant influence on the enthalpy of adsorption fingerprint. A comparison of the materials studied with those reported in the literature allowed us to propose a set of guidelines for the design of polymers for CO2 capture applications.

Supramolecular materials are important due to their distinct physical and chemical properties. Here we report the synthesis and structural determination, by single-crystal X-ray diffraction, of five new supramolecular networks, namely {[Fe(bpy)(3)OH][dca center dot 4H(2)O]}(n) (1), {[Fe(bpy)(3)][Zn(dca)(3)](2)}(n) (2), {Zn(bpy)(2)(dca)(2)}(n) (3), {Zn(bpy)(dca)(2)}(n) (4) and {[Zn(bpy)(3)][Fe(dca)(3)](2)}(n) (5), where bpy = bipyridine and dca = dicyanamide. Compound 1 is made up of a [Fe(bpy)(3)OH](+) cation layer and a [dca center dot 4H(2)O](-) anion layer. Water clusters are present in the anionic sheet which link adjacent layers of the supramolecular assembly of compound 1. The anionic layer consists of randomly orientated dca anions and water clusters, while the cationic layer has randomly occupied OH groups. Compounds 2 and 5 have similar molecular connectivity to a previously reported structure, but with a different combination of metal centres. They contain a two-dimensional {[M'(dca)(3)(-)}(n) network which provides perfect hexagonal pockets for [M(bpy)(3)](2+) cations. Compound 3 consists of neutral distorted octahedral monomeric units and these monomeric units are connected through intermolecular hydrogen bonding, forming a 3D network. One of anionic dca ligands in compound 3 is also randomly orientated. Compound 4 possesses a zig-zag 1D chain structure and a 3D framework is generated through weak interactions between aromatic rings of adjacent layers. All five compounds contain both bpy and dca. The crystallization of these compounds depends highly on the experimental conditions. (C) 2013 Elsevier Ltd. All rights reserved.

[trans-Cu(mu-OH)(mu-dmpz)](6) (1) exhibits six Cu(II) centers effectively coupled through a ligand mediated mechanism leading to a diamagnetic ground state over a wide temperature range. Here we investigate further magneto-structural correlations based on the possible free electron precession along such a copper-based ring-like nanocoil mediated by bridging ligands. We find that in 1, mediated antiferro-magnetic coupling leads to characteristics that induce aromatic ring behavior through evaluation of both induced currents and shielding of cones from a relativistic density functional theory level. According to our gauge calculations including magnetically induced current densities and an induced magnetic field, a sizable ring current strength susceptibility is obtained for the cyclic Cu-N-N-Cu and Cu-O-Cu pathways, allowing a magnetic exchange between the copper centers. Our study suggests that [Cu-6(dmPz)(6)(OH)(6)] consisting of an aromatic ring structure displays aromaticity and superexchange along the Cu-O-Cu and Cu-N-N-Cu backbones, which accounts for 80% and 20% of the overall ring current strength susceptibility, respectively. This reveals the presence of particular aromatic ring characteristics in coordination compounds without a direct metal-metal bond, where several formally paramagnetic centers are antiferromagnetically-coupled through supporting ligands. We envisage that our findings can be extended to other examples depicting ligand-mediated interaction between metal centers.

Twisted two-dimensional aromatic frameworks have been prepared by overcrowding the nodes with bulky and rigid substituents. The highly distorted aromatic framework with alternating out-of-plane substituents results in diminished interlayer interactions that favor the exfoliation and dispersion of individual layers in organic media. We are grateful to the Basque Science Foundation for Science (Ikerbasque), POLYMAT, the University of the Basque Country (SGIker), the Deutsche Forschungsgemeinschaft (AU 373/3-1 and MA 5215/4-1), Gobierno de Espana/FEDER (Ministerio de Economia y Competitividad, CTQ2015-71936-REDT, CTQ2016-77970-R, and ENE2015-66975-C3), Gobierno Vasco (BERC program, PC2015-1-01(06-37), and IT1069-16), Diputacion Foral de Guipuzkoa (2015-CIEN-000054-01), CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT ref. UID/CTM/50011/ 2013), ON2 (NORTE-07-0162-FEDER-000086), the Fund of Scientific Research-Flanders (FWO), the Internal Funds KU Leuven, the Belgian Federal Science Policy Office (IAP-7/05), and the Nanoscale and Microscale Research Centre (NMRC, University of Nottingham, UK) for access to TEM. We have received funding for the research leading to these results from the European Union Seventh Framework Programme as a European Research Area Action (ERA-Chemistry) and a Marie Curie Action (Career Integration Grant No. 618247) and from the European Union Framework Programme for Research and Innovation Horizon 2020 as a Future and Emerging Technologies Action (FET Open) under Grant Agreement No. 664878 (2D-INK).

The five metal azolate/carboxylate (MAC) compounds [Cd(dmpzc)(DMF)(H2O)] (Cd-dmpzc), [Pd(H2dmpzc)2Cl2] (Pd-dmpzc), [Cu(Hdmpzc)2] (Cu-dmpzc), [Zn4O(dmpzc)3]·Solv (Zn-dmpzc·S), and [Co4O(dmpzc)3]·Solv (Co-dmpzc·S) were isolated by coupling 3,5-dimethyl-1H-pyrazol-4-carboxylic acid (H2dmpzc) to cadmium(II), palladium(II), copper(II), zinc(II), and cobalt(II) salts. While Cd-dmpzc and Pd-dmpzc had never been prepared in the past, for Cu-dmpzc, Zn-dmpzc·S, and Co-dmpzc·S we optimized alternative synthetic paths that, in the case of the copper(II) and cobalt(II) derivatives, are faster and grant higher yields than the previously reported ones. The crystal structure details were determined ab initio (Cd-dmpzc and Pd-dmpzc) or refined (Cu-dmpzc, Zn-dmpzc·S, and Co-dmpzc·S) by means of powder X-ray diffraction (PXRD). While Cd-dmpzc is a nonporous 3D MAC framework, Pd-dmpzc shows a 3D hybrid coordination/hydrogen-bonded network, in which Pd(H2dmpzc)2Cl2 monomers are present. The thermal behavior of the five MAC compounds was investigated by coupling thermal analysis to variable-temperature PXRD. Their catalytic activity was assessed in oxidative and C-C coupling reactions, with the copper(II) and cadmium(II) derivatives being the first nonporous MAC frameworks to be tested as catalysts. Cu-dmpzc is the most active catalyst in the partial oxidation of cyclohexane by tert-butyl hydroperoxide in acetonitrile (yields up to 12% after 9 h) and is remarkably active in the solvent-free microwave-assisted oxidation of 1-phenylethanol to acetophenone (yields up to 99% at 120 °C in only 0.5 h). On the other hand, activated Zn-dmpzc·S (Zn-dmpzc) is the most active catalyst in the Henry C-C coupling reaction of aromatic aldehydes with nitroethane, showing appreciable diastereoselectivity toward the syn-nitroalkanol isomer (syn:anti selectivity up to 79:21).

A series of mixed metal oxides (MMOs) adsorbents (MgAl-, CuAl- and CoAl-MMOs) were supported on graphene oxide (GO) through in-situ precipitation of layered double hydroxides (LDHs) onto exfoliated GO, followed by thermal conversion. The study shows that GO is an excellent support for the LDH-derived MMOs due to matching geometry and charge complementarity, resulting in a strong hybrid effect, evidenced by significantly enhanced adsorption performance for the commercially important removal of heavy thiophenic compounds from hydrocarbons. Fundamental liquid-phase adsorption characteristics of the MMO/GO hybrids are quantified in terms of adsorption equilibrium isotherms, selectivity and adsorbent regenerability. Upon incorporation of as little as 5 wt% GO into the MMO material, the organosulfur uptake was increased by up to 170%, the recycling stability was markedly improved and pronounced selectivity for thiophenic organosulfurs over sulfur-free aromatic hydrocarbons was observed.

A heterotetranuclear Na2Eu2 complex with uncommon photo-luminescence properties is reported. The complex exhibits good emission efficiency at ambient temperature, coupled with strong temperature dependence of the emission intensity and lifetime in the 273-333 K range, all of which are key features for non-contact luminescence-based thermometers capable of sensing and imaging temperatures in the physiological range.

The hybrid frameworks M 2 dobdc (dobdc 4− = 2,5-dioxidoterephthalate, M 2+ = Mg 2+ , Co 2+ , Ni 2+ , Cu 2+ and Zn 2+ ), commonly known as CPO-27 or MOF-74, are shown to be active catalysts in base-catalyzed reactions such as Knoevenagel condensations or Michael additions. Rather than utilizing N-functionalized linkers as a source of basicity, the intrinsic basicity of these materials arises from the presence of the phenolate oxygen atoms coordinated to the metal ions. The overall activity is due to a complex interplay of the basic properties of these structural phenolates and the reactant binding characteristics of the coordinatively unsaturated sites. The nature of the active site and the order of activity between the different M 2 dobdc materials were rationalized via computational efforts; the most active material, both in theory and in experiment, is the Ni-containing variant. The basicity of Ni 2 dobdc was experimentally proven by chemisorption of pyrrole and observation by IR spectroscopy.

Two new layered transition metal carboxylate frameworks, [Co-3(L)(2)(H2O)(6)]center dot 2H(2)O (1) and [Ni-3(L)(2)(H2O)(6)]center dot 2H(2)O (2) (L = tartronate anion or hydroxymalonic acid), have been synthesized and characterized by X-ray single crystal analysis. Both compounds have similar 2D structures. In both compounds there are two types of metal centers where one center is doubly bridged by the alkoxy oxygen atoms through mu(2)-O bridging to form a 1D infinite chain parallel to the crystallographic b-axis with the corners shared between the metal polyhedra. Magnetic susceptibility measurements revealed the existence of antiferromagnetic short range correlations between Co(Ni) intra-chain metal centers (with exchange constants J(Co) = -22.6 and J(Ni) = -35.4 K). At low temperatures, long range order is observed in both compounds at Neel temperatures of 11 (for 1) and 16 (for 2) K, revealing that other exchange interactions, rather than the intra-chain ones, play a role in these systems. Whereas compound 1 has an antiferromagnetic ground state, compound 2 exhibits a ferromagnetic component, probably due to spin canting. Isothermal magnetization data unveiled a rich phase diagram with three metamagnetic phase transitions below 8 K in compound 1.

High-performance membranes are attractive for molecular-level separations in industrial-scale chemical, energy and environmental processes. The next-generation membranes for these processes are based on molecular sieving materials to simultaneously achieve high throughput and selectivity. Membranes made from polymeric molecular sieves such as polymers of intrinsic microporosity (pore size

A series of isostructural metal-organic framework polymers of composition [Cu2(L)(H2O)2] (L= tetracarboxylate ligands), denoted NOTT-nnn, has been synthesized and characterized. Single crystal X-ray structures confirm the complexes to contain binuclear Cu(II) paddlewheel nodes each bridged by four carboxylate centers to give a NbO-type network of 64.82 topology. These complexes are activated by solvent exchange with acetone coupled to heating cycles under vacuum to afford the desolvated porous materials NOTT-100 to NOTT-109. These incorporate a vacant coordination site at each Cu(II) center and have large pore volumes that contribute to the observed high H2 adsorption. Indeed, NOTT-103 at 77 K and 60 bar shows a very high total H2 adsorption of 77.8 mg g(-)- equivalent to 7.78 wt% [wt% = (weight of adsorbed H2)/(weight of host material)] or 7.22 wt% [wt% = 100(weight of adsorbed H2)/(weight of host material + weight of adsorbed H2)]. Neutron powder diffraction studies on NOTT-101 reveal three adsorption sites for this material: at the exposed Cu(II) coordination site, at the pocket formed by three {Cu2} paddle wheels, and at the cusp of three phenyl rings. Systematic virial analysis of the H2 isotherms suggests that the H2 binding energies at these sites are very similar and the differences are smaller than 1.0 kJ mol-1, although the adsorption enthalpies for H2 at the exposed Cu(II) site are significantly affected by pore metrics. Introducing methyl groups or using kinked ligands to create smaller pores can enhance the isosteric heat of adsorption and improve H2 adsorption. However, although increasing the overlap of potential energy fields of pore walls increases the heat of H2 adsorption at low pressure, it may be detrimental to the overall adsorption capacity by reducing the pore volume.

9 pages; International audience; Four three-dimensional (3D) metal-organic frameworks [Mn3(3-Me-sal)4(py)4]n (1), [Mn3(4-Me-sal)4(py)4- (MeOH)]n * n(H2O) (2), [Mn3(5-Me-sal)4(py)4(H2O)2]n * n(MeOH) (3), and [Mn3(3-Me-sal)4(4-Me-py)4]n (4) and the one-dimensional (1D) coordination polymer {[Mn2(4-Me-sal)2(4-Me-py)2(H2O)2(MeOH)2][Mn(4-Me-sal)2(4-Me-py)2]}n (5) have been synthesized, where x-Me-salH2 ) x-methyl salicylic acid (x ) 3, 4, 5), py ) pyridine, and 4-Me-py ) 4-methyl-pyridine. The 3D frameworks of compounds 1-4 can be described as diamondoid networks. Magnetic studies show that weak MnII-MnIII antiferromagnetic interactions (in the range of -0.55 to -0.22 K) mediated by syn-anti carboxylate bridges are present in all compounds. While 5 remains paramagnetic down to 1.8 K, the 3D networks exhibit long-range ferrimagnetic ordering below 7.4 K for 1, 4.6 K for 2, 3.0 K for 3, and 7.7 K for 4. The decrease of the critical temperature reflects the increase of the coordination number around the Mn(II) site from four in 1, five in 2, and six in 3 that lower the bond strength and the magnetic interactions. This result also reinforces the hypothesis that the structures of 1 and 4 are similar as suggested by the X-ray analysis.