Sourav Das

This work demonstrates a multifunctional heterometallic Co( ii )–Y( iii )–Co( ii ) platform bridging molecular magnetism and energy-related catalysis.

This review highlights the latest developments in transition metal-based molecular catalysts for the oxygen reduction reaction, focusing on their design, electrochemical performance, challenges and perspectives on their potential applications.

The synthesis of efficient electrocatalysts for the oxygen evolution reaction (OER) in water splitting remains challenging due to slow reaction kinetics. In the present investigations, a novel octanuclear nickel(II) double cubane molecular cluster, [Ni ^II ₄ (LH ₃ ) ₃ ( µ ₃ ‐OH)( η ¹ ‐H ₂ O) ₂ ] ₂ ·2NO ₃ ·2H ₂ O·CH ₃ OH ( 3 ), has been synthesized using a Schiff‐base ligand LH ₄ (2‐[2‐hydroxy‐3‐(hydroxymethyl)‐5‐methylbenzylideneamino]‐2‐methylpropane1,3‐diol). Complex 3 was immobilized on activated carbon cloth (CC), referred to as CC‐3 , and investigated as an electrocatalyst for the OER in an alkaline medium. Single‐crystal X‐ray diffraction revealed that complex 3 comprised two distorted cubane‐like [Ni ₄ ( µ ₃ ‐OR) ₃ ( µ ₃ ‐OH)] ⁺ cores interconnected by flexible pendant ─CH ₂ OH groups from the ligand. Electrochemical analysis showed that CC‐3 exhibited excellent OER activity in 1.0 m KOH, which was reflected in a low overpotential of 290 mV at 10 mA cm ^{− 2} with a Tafel slope of 48 mV dec ⁻¹ . The catalyst showed remarkable stability, undergoing negligible degradation after 2000 CV cycles and 20 h of chronoamperometric measurement. Mechanistic studies suggest the formation of catalytically active high‐valent Ni ³⁺ ─OH intermediates during the OER. Fe ³ ⁺ addition to the electrolyte enhanced OER activity, attributed to high‐valent reactive species stabilization. This work demonstrates polynuclear nickel complexes as effective molecular electrocatalysts for OER, providing insights into their catalytic mechanisms.

This review examines magneto-chiral dichroism (MChD) in 3d–4f complexes, where chirality couples with magnetism. Synergistic 3d/4f design boosts MChD for chiral spintronics and quantum tech, guided by rational synthesis and theory.

This review covers recent advances in five-coordinate Co ^II SIMs with trigonal bipyramidal and square pyramidal geometries, showing how these geometries influence magnetic anisotropy and magnetization dynamics.

Isostructural Co ^II –Ln ^III –Co ^II complexes with a pyridine-based bicompartmental ligand were synthesized. Magnetic studies reveal coupling between Co ^II zero-field splitting and Ln ^III anisotropy. Tb ^III and Dy ^III analogues exhibit zero-field relaxation.

Two mononuclear lanthanide complexes, [(L)Ln ^III (Ph ₃ PO)Cl]·CH ₃ OH] [Ln ^III = Dy ( 1 ) and Er( 2 )], are isolated employing a pyridine‐based ligand, [2,2′‐{(1 E , 1′ E )‐pyridine 2,6–diylbis(methaneylylidine}bis(azaneylylidine)diphenol] (H ₂ L) and triphenylphosphine oxide. Both complexes are characterized by single‐crystal X‐ray diffraction studies. Pseudo‐pentagonal bipyramidal geometry (pseudo‐ D _5h ) around the lanthanide centers in both complexes is confirmed through SHAPE analysis. Dynamic magnetic measurements revealed the single‐ion magnet behavior for both complexes. However, the energy barrier ( U _eff ) and relaxation time ( τ ₀ ) for complex 1 are extracted as U _eff = 34.77 K, τ ₀ = 8.07 × 10 ⁻⁷ s (considering both Orbach and Raman processes). These observed phenomena have been corroborated with the aid of CASSCF‐based ab initio calculations.