A ferromagnetically coupled pseudo-calixarene [Co16] wheel that self-assembles as a tubular network of capsules

Reaction of Co(OAc)₂·4H₂O and Hsal in a basic MeCN solution affords the hexadecanuclear wheel [Co₁₆(sal)₁₆(OAc)₁₆]·16MeCN (1·16MeCN) that displays ferromagnetic nearest neighbour exchange and has pseudo-calixarene character. Symmetry equivalent wheels self-assemble to form remarkable tubular networks of capsules in the extended structure.

Investigating the effect of lanthanide radius and diamagnetic linkers on the framework of metallacrown complexes

By changing the stoichiometric ratios, the one-pot reaction of the glycinehydroxamic acid (H2glyha) ligand with copper(ii) and lanthanide(iii) salts in the presence of diamagnetic [Na2{Fe(CN)5(NO)}] led to two series of isostructural complexes, which can be designated as heterotrimetallic dimeric clusters [{LnCu5(glyha)5}{Fe(CN)5(NO)}(H2O)4]2·xNO3·yH2O (x = 2, y = 11 for La (1), x = 2, y = 11 for Pr (2), and x = 2, y = 11 for Nd (3)) and heterotetrametallic coordination polymers [Na{LnCu5(glyha)5}{Fe(CN)5(NO)}2(H2O)x·yH2O]n (x = 6, y = 4 for Sm (4), x = 6, y = 0 for Gd (5), x = 6, y = 4 for Tb (6), x = 5, y = 5 Dy (7), and x = 6, y = 4 for Ho (8)). Each molecular structure contains LnIII[15-metallacrown-5] nodes and diamagnetic [Fe(CN)5(NO)]2- linkers. The resulting products demonstrate diversified structural frameworks due to the radius effect of LnIII ions and different bridging fashions of diamagnetic [Fe(CN)5(NO)]2- linkers. An analysis of magnetic susceptibilities reveals that 7 exhibits ferromagnetic coupling between CuII and DyIII ions and field-induced SMM behavior.

Diazine based ligand supported CoII3 and CoII4 coordination complexes: role of anions

Synthesis of triple helical CoII4 and double helical CoII3 from diazine-based ligands and their magnetic behavior rationalized by susceptibility measurements.

Metal-Ion Induced In Situ Ligand Oxidation for Self-Assembled Clusters: from Bis(5-(2-pyridine-2-yl)-1,2,4-triazole-3-yl)methane to Alcohol or Ketone

Hydrothermal reactions of metal nitrates and ligand bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane (H₂ L¹ ) gave three cluster compounds, {Cr₂ }, {Zn₁₂ } and {Fe₈ }. Notably, methylene group of H₂ L¹ was in situ oxidized either to hydroxymethylated (L² -O)^3- in the metallo-ring {Zn₁₂ } or to a rigid carbonylated (L³ =O)^2- in the screw-type {Fe₈ }. In light of comparative experimental results, NO₃^- was deduced to be of a catalytic role in the ligand oxidation. Metal ion could be regarded as an "induced" tool for clusters generation in self-assembly process.

Crystal structure of dinuclear dichloridobis(dimethylformamide-kO)bis[μ2-3-(2-oxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazol-1ido-κ4-O,N:N′,N′′(2 − )]diiron(III) dimethylformamide (1/1), C36H42Cl2Fe2N14O6

C36H42Cl2Fe2N14O6, monoclinic, P21/c (no. 14), a = 10.44(4) Å, b = 9.13(3) Å, c = 22.46(7) Å, β = 100.88(4)°, V = 2101(12) Å3, Z = 2, R gt(F) = 0.0599, wR ref(F 2) = 0.1563, T = 296(2) K.

Solvent-mediated preparation of a heterometallic [2 × 2] grid via a 1D metal–organic template with extraordinary acid/base-resistance

Here, we have demonstrated that a metal–organic chain can serve as a template to prepare a heterometallic [2 × 2] grid through a solvent-mediated strategy.

Di- and octa-nuclear dysprosium clusters derived from pyridyl-triazole based ligand: {Dy2} showing single molecule magnetic behaviour

Dy^III-based two complexes, {Dy₂} (1) and {Dy₈} (2), were successfully isolated with H₂bpte ligand. In 1, H₂bpte bears trans,trans- while in 2 has cis,cis- coordination modes. {Dy₂} displays the single-molecule magnet behaviour with an energy barrier U_eff = 59(4) K.

Aggregation of the metallocycles {Cu8} and {Cu20} using [Cu(bp)] units (H2bp = bis(2-hydroxybenzyl)amine): structures and magnetic properties

Two metallocycles, {Cu8(bp)4(OH)4(H2O)4(ClO4)4} (1) and {Cu20(bp)20} (2), were afforded by the reactions of the semi-flexible tridentate ligand bis(2-hydroxybenzyl)amine (H2bp) with Cu(ClO4)2·6H2O and Cu(OAc)2·H2O. Complex 1 has a saddle-shaped cyclic structure and complex 2 has a nanosized wheel-shaped structure. The two compounds consist of [Cu(bp)] units.

A single-stranded {Gd18} nanowheel with a symmetric polydentate diacylhydrazone ligand

A {Gd₁₈} nanowheel was solvothermally synthesized. It features a rare single-stranded skeleton that looks like a Reuleaux triangle with vertices buckled in, represents the highest nuclearity and the largest size in any pure Ln wheels reported, and shows a large MCE.

A family of 12-azametallacrown-4 structural motif with heterometallic Mn(III) -Ln-Mn(III) -Ln (Ln=Dy, Er, Yb, Tb, Y) alternate arrangement and single-molecule magnet behavior

Mixed 3d-4f 12-azametallacrown-4 complexes, [Mn2 Ln2 (OH)2 (hppt)4 (OAc)2 (DMF)2 ]⋅2 DMF⋅H2 O [Ln=Dy (1), Er (2), Yb (3), Tb (4) and Y (5), H2 hppt=3-(2-hydroxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole)], were synthesized by reactions of H2 hppt with Mn(OAc)2 ⋅4 H2 O and Ln(NO3 )3 ⋅6 H2 O. This is the first 3d-4f azametallacrown family to incorporate Ln ions into the ring sets. These isostructural complexes exhibit alternating arrangements of two Mn and two Ln ions in the rings with each pair of metal centers bound by an NN group and μ2 -O bridging. Magnetic measurements revealed dominant antiferromagnetic interactions between metal centers, and frequency-dependent out-of-phase (${\chi {^\prime}{^\prime}_{\rm{M}} }$) signals below 4 K suggest slow relaxation of magnetization.

Structure modulation in zinc–ditetrazolate coordination polymers by in situ ligand synthesis

Three new coordination polymers have been constructed by an in situ ditetrazolate-ligand synthesis system involving the sharpless [2 + 3] cycloaddition reaction between IPN and NaN₃ in the presence of Zn²⁺ ions as Lewis-acid catalysts.

Construction of Fe6, Fe8 and Mn8 metallamacrocyclic complexes and magnetic properties

Hexanuclear-based 1 and octanuclear metallamacrocycle-based three-dimensional isostructural framework 2 and 3 have been obtained and characterised. Magnetic susceptibility measurements show that the three complexes display antiferromagnetic couplings.

Metal–organic frameworks based on rigid ligands as separator membranes in supercapacitor

Two MOFs are used as separator membranes in a supercapacitor, and after a charge–discharge experiment the separator membrane of the Co compound becomes more porous.

1D–3D mixed-ligand frameworks with an unusual dmp topology tuned by intersection angles of isomeric benzenedicarboxylates: magnetic properties, gas-dependent calcination-thermolysis and energy storage performances

Three coordination polymers with isomeric ligands were studied and used to prepare CoO and Co₃O₄ particles.

22-Azametallacrown-8 complex with a triazole-bridged ligand: synthesis, structure and magnetic properties

Reaction of Mn(OAc)2·4H2O with the H2L ligand affords a new manganese 22-MC-8 azametallacrown [Mn8(μ3-O)2(μ3-OH)2(μ2-OH)2(L)6(OAc)2(OH2)4]·2DMF (H2L = 3-(2-oxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole). The structural analysis of the complex reveals that the azaMC ring possesses -[Mn-O-Mn-N-N-Mn-N-N-Mn-N-N]- connectivity. The magnetic behavior of the complex shows the dominant antiferromagnetic interactions between the manganese ions with S = 4 and the frequency-dependent out-of-phase signal.

Structural modulation in two CuII-based MOFs by synergistic assembly involving the mixed-ligand synthetic strategy and the solvent effect

A synergistic assembly involving the mixed-ligand synthetic strategy and the solvent effect was successfully applied to tune two Cu^II-based MOFs. 1 represents a cds topology, while 2 is built by three distinct {Cu₄} clusters as SBUs.

Doping cobalt into a [Zn7] cluster-based MOF to tune magnetic behaviour and induce fluorescence signal mutation

An in situ doping strategy was successfully applied to tune the magnetic behaviour and induce fluorescence signal mutation of a spindle heptanuclear zinc cluster-based MOF, which led to a new Co^II-doped Zn^II-MTV-M′MOF with canted antiferromagnetism and weaker fluorescence emissions.