A series of rhombus-shaped Ln4 clusters: Syntheses, structures, luminescence properties and the SMM behavior of the Dy4 analogue

Abstract A series of tetranuclear lanthanide(III) clusters, namely, [Ln 4 ( μ 3 -OH) 2 L 6 (acac) 4 ]· x CH 3 CN (Ln(III) = Tb( 1 ), Dy( 2 ) and Ho( 3 ), HL = 5-(4-o-hydroxybenzylidene)-8-hydroxylquinoline; acac = acetylacetone), have been synthesized and completely characterized. The X-ray structural analysis exhibit that clusters 1 – 3 contain one Ln 4 center with rhombus-shaped arrangement, and each Ln(III) ion of them is located in a distorted square-antiprismatic coordination sphere. Magnetic measurements indicated that single molecule magnets behaviors were observed in 2 , with energy barrier (Δ E / k B ) of 55.17 K and τ 0  = 8.19 × 10 −7  s. Additionally, luminescence properties study reveal that 1 and 2 display the characteristic Tb III and Dy III luminescence at room temperature.