Fully earth‐abundant and highly efficient systems for producing syngas CO/H₂through photocatalytic reduction from CO₂are essential to approach a sustainable way of closing the carbon cycle. Herein, the synthesis and characterization of a new iron complex, Fe^IIL(NCS)₂py, coordinated to an N,N,N‐pincer ligand 2,6‐bis(4’‐phenyl‐1’,2’,3’‐triazol‐1’‐yl‐methyl)pyridine (L), two isothiocyanate groups (NCS) and one pyridine is reported. Its catalytic activity in the photo‐driven reduction of carbon dioxide has been investigated and compared with its Co^IIanalogue (CoL(NCS)₂py) and their homoleptic complexes ML₂. In this work, the catalysts are used in combination with the heteroleptic complex [Cu^I(dmp)(DPEphos)], where dmp is 2,9‐dimethyl‐1,10‐phenanthroline and DPEPhos is bis[(2‐diphenylphosphino)phenyl] ether, to reach entirely earth‐abundant systems. The new iron heteroleptic complex Fe^IIL(NCS)₂py showed considerable activity with a TON_COof 576 obtained after 4 h (TOF=144 h⁻¹) through visible light (λ=420 nm) and a quantum yield of 7.1 %.

The [Gd₈(opch)₈(CO₃)₄(H₂O)₈]·4H₂O·10MeCN coordination cluster (1) crystallises in $P\overline{1}$. The Gd₈ core is held together by four bridging carbonates derived from atmospheric CO₂ as well as the carboxyhydrazonyl oxygens of the 2-hydroxy-3-methoxybenzylidenepyrazine-2-carbohydrazide (H₂opch) Schiff base ligands. The magnetic measurements show that the Gd^III ions are effectively uncoupled as seen from the low Weiss constant of 0.05 K needed to fit the inverse susceptibility to the Curie–Weiss law. Furthermore, the magnetisation data are consistent with the Brillouin function for eight independent Gd^III ions. These features lead to a magnetocaloric effect with a high efficiency which is 89% of the theoretical maximum value.

We report the synthesis, structures and magnetic behaviour of two isostructural dinuclear Dy³⁺ complexes where the metal ions of a previously reported monomeric building block are connected by a peroxide (O₂²⁻) or a pair of fluoride (2×F⁻) bridges. The nature of the bridge determines the distance between the metal ion dipoles leading to a dipolar coupling in the peroxido bridged compound of only ca. 70 % of that in the bis‐fluorido bridged dimer. The sign of the overall coupling between the metals is antiferromagnetic for the peroxido bridged compound and ferromagnetic for the bis‐fluorido bridged complex. This in turn influences the magnetisation dynamics. We compare the relaxation characteristics of the dimers with those of the previously reported monomeric building block. The relaxation dynamics for the bis‐fluorido system are very fast. On the other hand, comparing the properties of the monomer, the peroxido bridged sample and the corresponding Y‐doped sample show that the relaxation properties via a Raman process have very similar parameters. We show that a second dysprosium is important for either tuning or detuning the Single Molecule Magnet (SMM) properties of a system.

The evaluation of the magnetic hysteresis of a saddle-shaped Fe ₈ Dy ₁₂ cyclic coordination cluster (CCC) using MAGELLAN reveals three sets of Dy ^III anisotropy axes.

Copper complexes have shown great versatility and a wide application range across the natural and life sciences, with a particular promise as organic light-emitting diodes. In this work, four novel heteroleptic Cu(I) complexes were designed in order to allow their integration in advanced materials such as metallopolymers. We herein present the synthesis and the electrochemical and photophysical characterisation of these Cu(I) complexes, in combination with ab initio calculations. The complexes present a bright cyan emission (λ_em ~ 505 nm) in their solid state, both as powder and as blends in a polymer matrix. The successful synthesis of metallopolymers embedding two of the novel complexes is shown. These copolymers were also found to be luminescent and their photophysical properties were compared to those of their polymer blends. The chemical nature of the polymer backbone contributes significantly to the photoluminescence quantum yield, paving a route for the strategic design of novel luminescent Cu(I)-based polymeric materials.

Within the framework of 3d–4f molecular magnets, the most thoroughly investigated architecture is that of butterfly‐shaped coordination clusters as it provides an ideal testbed to study fundamental magnetic interactions. Here, we report the synthesis and characterisation of a series of isostructural V^III₂Ln^III₂ butterfly complexes, where Ln=Y (1_Y), Tb (2_Tb), Dy (3_Dy), Ho (4_Ho), Er (5_Er), Tm (6_Tm), Yb (7_Yb), which extends the previous study on isostructural butterflies with Cr^III, Mn^III and Fe^III. In zero external field, compounds 2_Tb, 3_Dy and 4_Ho show clear maxima in the out‐of‐phase component of the ac susceptibility whereas small magnetic fields are needed to suppress quantum tunnelling in 6_Tm. Combined high‐field electron paramagnetic resonance spectroscopy and magnetisation measurements unambiguously reveal an easy‐plane anisotropy of the V^III ion and antiferromagnetic Ising‐like 3d–4f exchange couplings. The strength of J_3d‐4f is shown to decrease upon variation of the 4 f ion from Tb to Ho, while increasing antiferromagnetic interaction can be observed from Ho to Tm. The exact inverse chemical trend is found for the relative angle between the 3d and 4 f main anisotropy axes, which highlights the important role of the lanthanide 4 f electron distribution anisotropy for 3d–4f exchange.