Nanoscale {LnIII(24)ZnII(6)} Triangular Metalloring with Magnetic Refrigerant, Slow Magnetic Relaxation, and Fluorescent Properties.

The self-assembly of Ln(ClO4)3 · 6H2O and Zn(OAc)2 · 2H2O with pyrazine-2-carboxylic acid (HL) results in the formation of three novel nanosized {LnIII(24)ZnII(6)} triangular metallorings, [Gd24Zn6L24(OAc)22(μ3-OH)30(H2O)14](ClO4)7(OAc) · 2CH3OH · 26H2O (1), [Tb24Zn6L24(OAc)22(μ3-OH)30(CH3O)2(CH3OH)2(H2O)10](ClO4)5(OH) · 6CH3OH · 12H2O (2), and (H3O)[Dy24Zn6L24(OAc)22(μ3-OH)30(H2O)14](ClO4)7(OAc)2 · 4CH3OH · 22H2O (3), having the largest nuclearity among any known Ln/Zn clusters. Magnetic and luminescent studies reveal the special prowess for each lanthanide complex. Magnetic studies reveal that 1 exhibits a significant cryogenic magnetocaloric effect with a maximum -ΔSm (isothermal magnetic entropy change) value of 30.

Employment of triketones to construct a dysprosium(III) single-molecule magnet.

The initial employment of a triketone ligand in 4f coordination chemistry afforded a series of dinuclear complexes. Magnetic studies revealed that an antiferromagnetic interaction exists in a digadolinium(III) compound, while a dysprosium(III) constructed complex exhibits single-molecule magnet (SMM) behaviour at low temperatures with an energy barrier of 86.8 K.