Linear shaped hetero-metallic [Zn2Ln4] clusters with Schiff base ligand: Synthesis, characterization and magnetic properties

A series of isostructural 3d-4f coordination clusters (CCs) [Zn2Ln4(L1)4(L2)2(OAc)2(N3)2] [Na2(OH2)2(NO3)3.2(N3)0.8]center dot 2MeCN, where Ln = Dy (1), Ho (2), Er (3), Tm (4), and Yb (5), L1 = 6-Methoxy-2-(2-pyridylmethyliminomethyl)phenol and L2 = (E)-2-methoxy-6-(2-((3-methoxy-2-oxidobenzylidene)amino)-1-oxido2-(pyridin-2-yl)ethyl)phenolate has been synthesised and structurally characterised. The magnetic properties of 1-5 have been investigated using dc and ac susceptibility measurements. The paramagnetic metal ions within the clusters are weakly antiferromagnetically coupled, with the Er and Dy compounds displaying slow relaxation of their magnetisation. This is the first report of this versatile ligand being used to target 3d-4f coordination clusters.