Structures, fluorescence properties and magnetic properties of a series of dinuclear lanthanide(III) compounds: Dy 2 compound showing single-molecule magnet behavior

Abstract A series of dinuclear lanthanide(III) compounds, namely, [Ln 2 (tmhd) 2 L 2 (CH 3 OH) 2 ] (Ln(III) = Sm ( 1 ), Eu ( 2 ), Dy ( 3 ) and Er ( 4 ); H 2 L = 2-amino-benzoic acid (8-hydroxy-quinolin-2-ylmethylene)-hydrazide, Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione), have been synthesized, structurally and magnetically characterized. The X-ray structural analysis exhibit that 1 – 4 are phenoxo-O-bridged dinuclear compounds and central Ln(III) ions are eight-coordinated with one bidentate tmhd − , one CH 3 OH and two μ 2 -O bridging Schiff base ligands. Magnetic measurements indicated that slow magnetic relaxation behaviors were observed in 3 , with energy barrier (Δ E / k B ) of 13.14 K and τ 0  = 4.58 × 10 −6  s, however, no out-of-phase ( χ ″) alternating current (ac) signals noticed in 1 , 2 and 4 . Additionally, solid-state luminescence properties reveal that 1 – 3 display the characteristic Ln III luminescence at room temperature.