Abstract:The employment of (E)-2-(2-hydroxy-3-methoxybenzylideneamino)phenol (H2L1) with Co(NO3)2 6H2O and LnCl3 x(H2O) afforded a family of hexanuclear heterometallic coordinationwhere Ln is Y(1), Gd (2), Dy (3) and Tb (4). All the compounds are stable in solution as confirmed by ESI-MS studies. The topology of these compounds can be described as a twisted boat-like and enumerated as 2,3,4M6-1. The use of (E)-2-(5-bromo-2-hydroxy-3-methoxybenzylideneamino)phenol (H2L2) with Co(NO3)2 6H2O and DyCl3 x(H2O) afforded an isoskeletal to 1 -. Magnetic studies performed in the temperature range 1.8 -300K show that compound 3 shows a slow magnetic relaxation.