Syntheses, structures, and magnetic properties of salen type Cu–Gd dimer and hexamer complexes with strong ferromagnetic interactions

Abstract Two salen type heteronuclear Cu–Gd complexes, namely, [(GdCuL 1 Cl 3 (CH 3 OH) 2 ] ( 1 ) and [Gd 2 Cu 4 L 2 4 Cl 2 (OH)](PF 6 ) 3 ( 2 ) (H 2 L 1  =  N , N ′-bis(2-hydroxy-3-methoxybenzylidene)-1,2-diaminocyclohexane and H 2 L 2  =  N , N ′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) have been isolated. X-ray crystallographic analysis shows that 1 is of a typical neutral heterodinuclear Cu–Gd structure, while 2 features an unusual ionic hexanuclear Cu–Gd structure. Magnetic analysis reveals the dominant ferromagnetic interactions within the clusters.