Old materials with new tricks: multifunctional open-framework materials

Electrical properties, conduction mechanism and modulus of diphosphate compounds

Rubidium aluminium diphosphate was synthesized by a conventional solid-state technique and its conduction properties determined by impedance spectroscopy.

Facile preparation of a hierarchically porous metal–organic nanocomposite with excellent catalytic performance

A hierarchical porous MOF nanocrystal, hpCuL (L = 2,4,6-tris(3,5-dicarboxylatephenylamino)-1,3,5-triazine) was prepared via a facile gel-aging process. This nanocomposite exhibits high catalytic activity and stability for the reduction of 4-nitrophenol.

The influence of different coordination environments on one-dimensional Cu(ii) coordination polymers for the photo-degradation of organic dyes

The role of coordination environment in 1D Cu(ii) coordination polymers for photo-catalytic activity has been investigated. Pyridine-2,6-dicarbohydrazide based polymeric complex 3 has the highest photo-catalytic rate constant (k = 0.72 h⁻¹) for rhodamine B degradation.

Self-assembly, binding ability and magnetic properties of dicopper(ii) pyrazolenophanes

The nature of the blocking α-diimine ligand controls of the molecular folding and binding ability of the resulting “butterfly-shaped”, antiferromagnetically coupled dicopper(ii) pyrazolenophanes in the solid state.

Exploiting redox activity in metal–organic frameworks: concepts, trends and perspectives

This feature article highlights latest developments in experimental, theoretical and computational concepts relevant to redox-active metal–organic Frameworks.

Molecular tectonics: dimensionality and geometry control of silver coordination networks based on pyrazolyl appended thiacalixarenes

Combinations of six new tetrakis-pyrazolyl appended calix[4]arenes derivatives, blocked in 1,3-A conformation as coordinating tectons, with AgX salts (X = NO₃⁻, BF₄⁻, XF₆⁻ (X = P, As and Sb)) lead to nine new silver coordination networks.

Inorganic nanoparticles in porous coordination polymers

This review highlights studies on the synthesis, characterization, and functions of the inorganic nanoparticles in porous coordination polymers.

Spin-crossover complex encapsulation within a magnetic metal–organic framework

We report the solid-state incorporation of a mononuclear iron(iii) spin-crossover (SCO) complex within the pores of a magnetic metal–organic framework (MOF).

Eight rare earth metal organic frameworks and coordination polymers from 2-nitroterephthlate: syntheses, structures, solid-state luminescence and an unprecedented topology

An unprecedented report of eight lanthanide(iii) CPs and MOFs from 2-nitroterephthalate which feature four network types, including one novel topology.

An open framework crystal structure and physical properties of RbCuAl(PO4)2

Single crystals of the RbCuAl(PO₄)₂ compound with an open 3D framework structure were obtained by a hydrothermal route. The compound orders antiferromagnetically at T_N = 10.5 K and exhibits spontaneous magnetization at lower temperature.

A 2D Semiquinone Radical-Containing Microporous Magnet with Solvent-Induced Switching from Tc = 26 to 80 K

The incorporation of tetraoxolene radical bridging ligands into a microporous magnetic solid is demonstrated. Metalation of the redox-active bridging ligand 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (LH2) with Fe(II) affords the solid (Me2NH2)2[Fe2L3]·2H2O·6DMF. Analysis of X-ray diffraction, Raman spectra, and Mössbauer spectra confirm the presence of Fe(III) centers with mixed-valence ligands of the form (L3)(8-) that result from a spontaneous electron transfer from Fe(II) to L(2-). Upon removal of DMF and H2O solvent molecules, the compound undergoes a slight structural distortion to give the desolvated phase (Me2NH2)2[Fe2L3], and a fit to N2 adsorption data of this activated compound gives a BET surface area of 885(105) m(2)/g. Dc magnetic susceptibility measurements reveal a spontaneous magnetization below 80 and 26 K for the solvated and the activated solids, respectively, with magnetic hysteresis up to 60 and 20 K. These results highlight the ability of redox-active tetraoxolene ligands to support the formation of a microporous magnet and provide the first example of a structurally characterized extended solid that contains tetraoxolene radical ligands.

Novel Applications for Oxalate-Phosphate-Amine Metal-Organic-Frameworks (OPA-MOFs): Can an Iron-Based OPA-MOF Be Used as Slow-Release Fertilizer?

A porous iron-based oxalate-phosphate-amine metal-organic framework material (OPA-MOF) was investigated as a microbially-induced slow-release nitrogen (N) and phosphorus (P) fertilizer. Seedling growth, grain yields, nutrient uptake of wheat plants, and soil dynamics in incubated soil, were investigated using OPA-MOF vs standard P (triple-superphosphate) and N (urea) fertilizers in an acidic Ferralsol at two application rates (equivalent 120 and 40 kg N ha(-1)). While urea hydrolysis in the OPA-MOF treatment was rapid, conversion of ammonium to nitrate was significantly inhibited compared to urea treatment. Reduced wheat growth in OPA-MOF treatments was not caused by N-deficiency, but by limited P-bioavailability. Two likely reasons were slow P-mobilisation from the OPA-MOF or rapid P-binding in the acid soil. P-uptake and yield in OPA-MOF treatments were significantly higher than in nil-P controls, but significantly lower than in conventionally-fertilised plants. OPA-MOF showed potential as enhanced efficiency N fertilizer. However, as P-bioavailability was insufficient to meet plant demands, further work should determine if P-availability may be enhanced in alkaline soils, or whether central ions other than Fe, forming the inorganic metal-P framework in the MOF, may act as a more effective P-source in acid soils.

Crystal structure of bis-(μ-2-benzoyl-benzoato-κ(2) O:O')bis-[bis-(2,2'-bi-pyridine-κ(2) N,N')manganese(II)] bis-(perchlorate)

The title compound, [Mn2(C6H5COC6H4COO)2(C10H8N2)4](ClO4)2, comprises a centrosymmetric binuclear cation and two perchlorate anions. In the complex cation, two Mn(II) atoms are bridged by two O atoms of two different 2-benzoyl-benzoate ligands, each Mn(II) atom being further coordinated by two 2,2'-bi-pyridine (bipy) ligands in a distorted octa-hedral environment. Within the binuclear mol-ecule, the Mn⋯Mn separation is 4.513 (7) Å. Inter-molecular C-H⋯O and C-H⋯ π inter-actions link the mol-ecules into a three-dimensional network.

Multidimensional transition metal complexes based on 3-amino-1H-1,2,4-triazole-5-carboxylic acid: from discrete mononuclear complexes to layered materials

The synthesis and structural characterization of five transition metal complexes with different dimensionality and incorporating residues of 3-amino-1H-1,2,4-triazole-5-carboxylic acid (H₂atrc) is reported: [Zn(Hatrc)₂(H₂O)] (1), [Mn(Hatrc)₂(H₂O)₂]·2H₂O (2), [Fe₂(Hatrc)₄(OH)₂]·6H₂O (3), [Cd(Hatrc)₂(H₂O)]_n (4), and [Mn(atrc)(H₂O)]_n·nH₂O (5). These materials could be prepared from solution (1–3), diffusion (4), or hydrothermal reactions (5) with various anions and L:M ratios. Structural details were revealed by single crystal X-ray diffraction. The discrete units composing compounds 1–3, the polymeric 1D chain of 4 and the 2D layer of 5 are further extended into 3D supramolecular architectures through the formation of hydrogen bonds.

Ln-Ag heterometallic coordination polymers

The last few years have seen an increasing interest in the study of lanthanide-silver (Ln-Ag) heterometallic coordination polymers due to their potential applications. It has led to intense activity of chemists to produce Ln-Ag heterometallic coordination polymers and investigate their properties. In this review, we summarize recent research development in the fascinating and challenging field of Ln-Ag heterometallic coordination polymers. This review covers 182 Ln-Ag heterometallic coordination polymers, which are categorized by the kind of ligand as N-heterocyclic carboxylate ligands and others. There are three categories of Ln-Ag coordination polymer based on N-heterocyclic carboxylate ligands: one dimensional (1D), 2D, and 3D. The 3D part was divided into Ln-Ag coordination polymers based on pyridine carboxylate ligands and other N-heterocyclic carboxylate ligands. This perspective illustrates the coordination features of compounds constructed by N-heterocyclic carboxylate ligands. Luminescent properties are also discussed.

A "green" strategy to construct non-covalent, stable and bioactive coatings on porous MOF nanoparticles

Nanoparticles made of metal-organic frameworks (nanoMOFs) attract a growing interest in gas storage, separation, catalysis, sensing and more recently, biomedicine. Achieving stable, versatile coatings on highly porous nanoMOFs without altering their ability to adsorb molecules of interest represents today a major challenge. Here we bring the proof of concept that the outer surface of porous nanoMOFs can be specifically functionalized in a rapid, biofriendly and non-covalent manner, leading to stable and versatile coatings. Cyclodextrin molecules bearing strong iron complexing groups (phosphates) were firmly anchored to the nanoMOFs' surface, within only a few minutes, simply by incubation with aqueous nanoMOF suspensions. The coating procedure did not affect the nanoMOF porosity, crystallinity, adsorption and release abilities. The stable cyclodextrin-based coating was further functionalized with: i) targeting moieties to increase the nanoMOF interaction with specific receptors and ii) poly(ethylene glycol) chains to escape the immune system. These results pave the way towards the design of surface-engineered nanoMOFs of interest for applications in the field of targeted drug delivery, catalysis, separation and sensing.

Three luminescent metal–organic frameworks constructed from trinuclear zinc(ii) clusters and furan-2,5-dicarboxylate

Three metal–organic frameworks constructed from trinuclear zinc(ii) clusters and furan-2,5-dicarboxylate with different topology were hydrothermally synthesized by adjusting the anions and solvent. Moreover, the blue luminescence of the complexes was investigated.

Magnetic properties of manganese based one-dimensional spin chains

Magnetic susceptibility and heat capacity of three manganese based structures are measured and modeled with one-dimensional antiferromagnetic chains.

Spontaneous symmetry breaking of Co(ii) metal–organic frameworks from achiral precursors via asymmetrical crystallization

Enantioenriched 3D pseudo-enantiomorphs integrating porosity, chirality and magnetism together with different colour and morphology were obtained through spontaneous symmetry breaking.

Heterometallic coordination polymers: syntheses, structures and heterogeneous catalytic applications

Heterometallic coordination polymers function as heterogeneous catalysts for various organic transformation reactions via preferential interaction with the substrates.

LnIII ion dependent magnetism in heterometallic Cu–Ln complexes based on an azido group and 1,2,3-triazole-4,5-dicarboxylate as co-ligands

Four Cu–Ln coordination polymers [Cu₂Ln(tda)₂N₃(H₂O)₄·2H₂O] (Ln = Gd (1), Tb (2), Dy (3), Sm (4), tda = 1,2,3-triazole-4,5-dicarboxylate) have been synthesized by employing H₃tda and azido as co-ligands.