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The combination of two different FeIII salts in a solvothermal reaction with triethanolamine results in the formation of a high symmetry [Fe III15 ] cluster whose structure conforms to a centred, tetrakis hexahedron. [ABSTRACT FROM AUTHOR]

The adiabatic temperature change of the star-shaped {CoIII3GdIII3} magnetocaloric ring is enhanced via topological control over the assembly process, by using a pre-formed {CoII(H6L)} building block that undergoes oxidation to CoIII, successfully separating the GdIII ions. [ABSTRACT FROM AUTHOR]

A family of interwoven molecular inorganic knots, shaped like the ‘Star of David’, was prepared by the employment of naphthalene-2,3-diol in 3d/4f-metal cluster chemistry; the isoskeletal dodecanuclear compounds exhibit slow relaxation of the magnetization and magnetocaloric properties, depending on the metal ion. [ABSTRACT FROM AUTHOR]

The reaction of [Cr3IIIO(OAc)6(H2O)3]NO3·AcOH with 2-hydroxynaphthaldehyde, 2-amino-isobutyric acid and NiCl2·6H2O in MeOH, under basic and solvothermal conditions, led to the formation of the quasi-1D coordination polymer {[CrIII2NiII(L)4(MeOH)2]}n (where L = the dianion of the Schiff base between 2-hydroxynaphthaldehyde and 2-amino-isobutyric acid), which behaves as a ferromagnetic chain, displaying slow relaxation of magnetization. [ABSTRACT FROM AUTHOR]

Layered gadolinium hydroxides have revealed to be excellent candidates for cryogenic magnetic refrigeration. These materials behave as pure 2D magnetic systems with a Heisenberg–Ising critical crossover, induced by dipolar interactions. This 2D character and the possibility offered by these materials to be delaminated open the possibility of rapid heat dissipation upon substrate deposition. [ABSTRACT FROM AUTHOR]

A CO32−-panelled [GdIII6CuII3] cage conforming to a tridiminished icosahedron is synthesised by bubbling CO2 through a solution of GdIII and CuII ions. [ABSTRACT FROM AUTHOR]

We report the rotational spectrum of one conformer of the tetramer of difluoromethane (CH2F2)4 (the first pure rotational spectrum of a tetramer of an asymmetric rotor), and describe the network of weak hydrogen bonds which connect the four subunits. [ABSTRACT FROM AUTHOR]

A novel diphenoxo-bridged Gd3+–Mn2+ dimer is proposed as a good candidate for cryogenic magnetic refrigeration. The large MCE is enhanced by the ferromagnetic interaction between the two metal ions. [ABSTRACT FROM AUTHOR]

The epoxidation of alkenes was carried out over a CuO/Al2O3 catalyst using cumene as an oxygen carrier, through a one-pot reaction, giving high conversion and selectivity with different substrates. Trans-β-methylstyrene gave the corresponding epoxide in 95% yield after 3 h. [ABSTRACT FROM AUTHOR]

This review explores calixarenes, a prominent family of third-generation supramolecules celebrated for their distinct hollow, cavity-shaped structures. These macrocycles are intricately assembled by linking multiple phenolic units orthogonally through methylene (–CH2–), sulfur (–S–), or sulfonyl (–SO2–) bridges. This structural framework plays a pivotal role in the intricate assembly of nanoclusters, significantly advancing the field of cluster chemistry. A key focus of current research is the remarkable ability of calixarenes to stabilize titanium-oxo clusters. Our review details the application of calixarenes in constructing titanium-oxo cluster structures, emphasizing how these clusters, when encapsulated within calixarenes, exploit flexible coordination sites for structural modifications and serve as foundational units for more complex assemblies. Additionally, we investigate how these calixarene-stabilized metal-oxo clusters function as versatile scaffolds for catalytically active metal ions, facilitating the creation of bimetallic nanoclusters. These clusters not only exhibit unique structural diversity but also demonstrate exceptional catalytic efficiency. This review aims to inspire ongoing exploration and innovation in the use of calixarenes for the synthesis and application of advanced cluster materials. [ABSTRACT FROM AUTHOR]

Use of the dicarboxylates iso-phthalate and succinate in the preparation of [Mn6] SMMs links the hexametallic units into 1D chains. [ABSTRACT FROM AUTHOR]

Magnetic cooling is a highly efficient refrigeration technique with the potential of replacing expensive and rare helium-3 in the field of ultra-low temperature cooling. However, the visualization of a cryogen at an extremely low temperature and in a strong magnetic field is challenging, but it is crucial for the precise positioning and in situ thermal probe measurements in potential practical applications. Here, the activation of a red-emissive Mn(ii) ion using 3d/4f chemistry produces a luminescent molecule cooler, [Gd5Mn2(LOMe)2(OH)4(Ac)6(MeOH)10Cl2]Cl3·2MeOH (1), with the core of an Mn(ii)-anchored heptanuclear [GdIII5MnII2] pyramid. The photoluminescence (PL) of the Mn2+ emission, with a large Stokes shift (λem∼ 690 nm) from 4T1(4G) →6A1(6S), shows not only a sensitive temperature sensing property but also reversible mechanoluminescence (ML). More attractively, these findings reveal a considerable magnetocaloric effect (MCE) coupled with a tunable emission window, opening up new opportunities in the multifunctional applications of PL, ML, and the MCE involving red-light sources, thermometers, and stress imaging. In particular, this provides a novel resolution to design visualized PL coolers. [ABSTRACT FROM AUTHOR]

Presented herein is a series of chain compounds based on pre-designed heterometallic aluminum–lanthanide (Al–Ln) Al4Ln4 molecular rings. Their photoluminescence quantum yield (PLQY) with Eu3+ (30.41%) and Tb3+ (41.44%) is at a high level among the clusters containing four Ln ions. This study significantly extends the family of Al–Ln heterometallic clusters and demonstrates the synergistic effect of heterometallic ions in enhancing their properties. [ABSTRACT FROM AUTHOR]

The neutral holmium(III) oxalate octadecahydrate {[Ho2(ox)3(H2O)6]·12H2O}n of mixed hexagonal/decagonal (63·103) 3D net topology shows important changes in the magnetocaloric efficiency upon dehydration/rehydration by heating and water vapor exposition to give the holmium(III) oxalate decahydrate {[Ho2(ox)3(H2O)6]·4H2O}n of hexagonal (63) 2D net topology through the intermediacy of the elusive amorphous anhydrous compound {Ho2(ox)3}n. [ABSTRACT FROM AUTHOR]

The oxime functional group is pivotal in chemistry, finding extensive applications in medical science, catalysis, organic functional group transformations, and the recognition of essential and toxic analytes. While the coordination chemistry of oxime derivatives has been thoroughly explored and several reviews have been published on this topic in reputable journals, a comprehensive review encompassing various aspects such as crystal engineering, cation and anion recognition, as well as coordination chemistry activities, is still in demand. This feature article highlights the diverse applications of oxime derivatives across multiple domains of chemistry, including medicine, agriculture, crystal engineering, coordination chemistry, and molecular recognition studies. Each of the oxime derivatives in this feature article are meticulously described in terms of their medicinal applications, crop protection, crystal engineering attributes, analyte recognition capabilities, and coordination chemistry aspects. By providing a comprehensive overview of their versatile applications, this article aims to inspire researchers to explore and develop novel oxime-based derivatives for future applications. [ABSTRACT FROM AUTHOR]

Dissolution of FeBr3 in a mixture of acetonitrile and 3,4-lutidine in the presence of an amine results in the formation of an [Fe30] molecular metal oxide containing alternating layers of tetrahedral and octahedral FeIII ions. Mass spectrometry suggests the cluster is formed quickly and remains stable in solution, while magnetic measurements and DFT calculations reveal competing antiferromagnetic exchange interactions. [ABSTRACT FROM AUTHOR]

Two unique 3D coordination polymers based on octahedral [Ln6] (Ln = Gd (1), Dy (2)) clusters as nodes were synthesized, exhibiting a novel (3,12)-connected topology with the symbol of (420·626·820)(43)4. The magnetic studies reveal that 1 shows a −ΔSm = 46.6 J kg−1 K−1, falling among the largest values known to date, and 2 displays slow magnetic relaxation behavior. Both 1 and 2 have high thermal and solvent stabilities. [ABSTRACT FROM AUTHOR]

Twenty years ago, I wrote a Chem. Commun. feature article entitled "Crystal Engineering: where from? Where to?": an update is in order. In this Highlight I argue that molecular crystal engineering, one of the areas of fast development of the field, has definitely reached the stage of "delivering the goods": new functional materials assembled via non-covalent interactions and/or improved properties of existing materials. As a proof of concept, the crystal engineering approach to tackle two contemporary emergencies, namely, urea fertilizer degradation and development of antimicrobial resistance by pathogens, is discussed and application-driven examples are provided. [ABSTRACT FROM AUTHOR]

The electronic states of iodo-bridged platinum nanowire complexes have been studied using polarized FT-IR spectroscopy. The N–H symmetrical stretching mode was found to be highly sensitive to the electronic states, distinguishing mixed-valence (MV) and averaged-valence (AV) states. The first Pt(III) nanowire complexes have been realized by the chemical pressures of the counter-anions. [ABSTRACT FROM AUTHOR]

Reaction of the 1,2,4,5-tetrazine (tz˙−) radical and {Cp*2Tb}+ has yielded a tetranuclear radical-bridged TbIII single-molecule magnet. The strong Ln–radical coupling and the electronic differences of the TbIII ions in [(Cp*2Tb)4(tz˙−)4]·3C6H6 (1) are probed via magnetic, magneto-optical and computational studies. [ABSTRACT FROM AUTHOR]

Lanthanide Single-Molecule Magnets (SMMs) fascinate the scientific community due to their plethora of potential applications ranging from data storage to spintronic devices and quantum computing. This review article proposes a comprehensive description of the influence of the nuclear spin, i.e. hyperfine interaction, on the magnetic properties of lanthanide SMMs and on quantum information processing of qudit. This influence is analysed for non-Kramers and Kramers lanthanide SMMs as well as for the electronic distribution of the electron in 4f orbitals i.e. oblate and prolate ions. Then the role of magnetic interactions in isotopically enriched polynuclear Dy(III) SMMs is discussed. Finally the possible effect of superhyperfine interaction due to the nuclear spin of elements originating from the surrounding of the lanthanide centre is analyzed. The effect of nuclear spin on the dynamics of the lanthanide SMMs is demonstrated using different techniques such as magnetometry, muon spectroscopy (μ-SR), and Mössbauer and Resonance Vibrational Spectroscopies. [ABSTRACT FROM AUTHOR]

Two 24-nuclear lanthanide clusters, Gd24 and Dy24 were obtained and structurally characterized. Magnetic investigations reveal that Gd24 exhibits the largest entropy change (−ΔSm) of 46.12 J kg−1 K−1 for ΔH = 7 T in all reported molecular clusters, and single-molecule magnet behaviour is observed in Dy24. [ABSTRACT FROM AUTHOR]

A family of nanosized {Cu6Ln12} clusters with a ‘windmill’-like topology was prepared from the employment of 2,6-diacetylpyridine dioxime, in conjunction with bridging N3−, in 3d/4f-metal chemistry; the octadecanuclear compounds exhibit single-molecule magnetism behavior and large magnetic entropy changes, depending on the 4f-metal ion present. [ABSTRACT FROM AUTHOR]

The layered allotropes of group 15 (P, As, Sb and Bi), also called two-dimensional (2D) pnictogens, have emerged as one of the most promising families of post-graphene 2D-materials. This is mainly due to the great variety of properties they exhibit, including layer-dependent bandgap, high charge-carrier mobility and current on/off ratios, strong spin–orbit coupling, wide allotropic diversity and pronounced chemical reactivity. These are key ingredients for exciting applications in (opto)electronics, heterogeneous catalysis, nanomedicine or energy storage and conversion, to name a few. However, there are still many challenges to overcome in order to fully understand their properties and bring them to real applications. As a matter of fact, due to their strong interlayer interactions, the mechanical exfoliation (top-down) of heavy pnictogens (Sb & Bi) is unsatisfactory, requiring the development of new methodologies for the isolation of single layers and the scalable production of high-quality flakes. Moreover, due to their pronounced chemical reactivity, it is necessary to develop passivation strategies, thus preventing environmental degradation, as in the case of bP, or controlling surface oxidation, with the corresponding modification of the interfacial and electronic properties. In this Feature Article we will discuss, among others, the most important contributions carried out in our group, including new liquid phase exfoliation (LPE) processes, bottom-up colloidal approaches, the preparation of intercalation compounds, innovative non-covalent and covalent functionalization protocols or novel concepts for potential applications in catalysis, electronics, photonics, biomedicine or energy storage and conversion. The past years have seen the birth of the chemistry of pnictogens at the nanoscale, and this review intends to highlight the importance of the chemical approach in the successful development of routes to synthesise, passivate, modify, or process these materials, paving the way for their use in applications of great societal impact. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis and chiroptical properties of 2-azatriptycenes and their platinum(II) complexes, which represent the first examples of heterotriptycenes and metallotriptycenes that exhibit circularly polarized fluorescence and phosphorescence (CPF and CPP). Theoretical studies for CPF and CPP strongly support the experimental findings. [ABSTRACT FROM AUTHOR]

The hypothetical [BiPh]− anion obtained by a one-electron reduction from the respective bismuthinidene is proposed as a basis for constructing single-molecule magnets (SMMs) consisting purely of main-group elements. Based on high-level quantum-chemical calculations, the [BiPh]− anion is predicted to be a SMM with an effective barrier of 6418 cm−1 for the relaxation of magnetization. This barrier is much larger than any effective barrier observed so far in any experimentally characterized SMM. The reduction potential for the [BiPh]−/BiPh couple is calculated as −1.5 V, which implies that the [BiPh]− moiety is accessible from stable bismuthinidenes containing a BiPh moiety and sufficient steric protection for the reactive Bi atom. Thus, [BiPh]− provides a blueprint for the realization of purely main-group SMMs which can surpass in their properties the best known dysprosium-based SMMs. [ABSTRACT FROM AUTHOR]

Tunable gold nanostars were synthesized through the reduction of gold salt by an aminosugar, N-methyl- D -glucamine, in a seed-less route. The nanoparticle morphology and size were facilely tuned through adjustments in reaction pH and LED light-mediated synthesis. The materials demonstrated low inherent cytotoxicity and high potential for photothermal therapy. [ABSTRACT FROM AUTHOR]

Metal formate frameworks [A][CrMn(HCOO)6] (A = CH3NH2CH3+ for 1 and CH3NH3+ for 2) with a large MCE were obtained, directed by the heterometallic strategy in which very weak magnetic interactions were achieved. A switch from antiferromagnetism to ferromagnetism occurs when replacing the CH3NH2CH3+ cation with CH3NH3+. The magnetic entropy change (−ΔSm) reached 48.20 J kg−1 K−1 for 2, which is the largest among the known polymeric 3d complexes. [ABSTRACT FROM AUTHOR]

High-valence Ti(IV)-based metallocalixarene coordination cages that are linked by oriented ancillary ligands are unknown so far. Herein, the first family of tunable calixarene-based coordination cages of Ti(IV) with a framework formula [Ti12(OiPr)12(TBC[4])6L6] have been assembled from six {Ti2(OiPr)2(TBC[4])}2+ nodes and six pyridinedicarboxylic ligands. Furthermore, the {Ti12L6} cage showed strong photocatalytic H2 evolution activity, and DFT studies were performed to explore its electronic structure. [ABSTRACT FROM AUTHOR]

Reaction between a carbazole-based mesoionic carbene ligand and manganese(II) iodide results in the formation of a rare air-stable manganese(IV) complex after aerobic workup. Cyclic voltammetry reveals the complex to be stable in five oxidation states. The electronic structure of all five oxidation states is elucidated chemically, spectroscopically (NMR, high-frequency EPR, UV-Vis, MCD), magnetically, and computationally (DFT, CASSCF). [ABSTRACT FROM AUTHOR]

Polyhedral metallocalixarene nanocage clusters based on pure Ti(IV) ions are to our knowledge unknown hitherto. Herein we report the first Ti(IV)-based metallocalixarene nanocage cluster by assembling a [Ti13O14] cage with six t-butylcalix[4]arene molecules. Notably, the cluster exhibits extraordinary stability in high-concentration acid/alkali solutions and can act as a stable photocatalyst to catalyze the oxidation of ammonia to imines. [ABSTRACT FROM AUTHOR]

Hydroxido-bridged Cu II6 M double-cubane clusters (M = MnII, CoII) supported by D -penicillaminedisulfide were unexpectedly formed by treating a D -penicillaminato Cu II2 Pt II2 complex with MBr2 in water. The clusters displayed heterogeneous electrocatalytic activities for water oxidation dependent on the central M shared by two CuII cubane units. [ABSTRACT FROM AUTHOR]