Investigating the effect of lanthanide radius and diamagnetic linkers on the framework of metallacrown complexes

By changing the stoichiometric ratios, the one-pot reaction of the glycinehydroxamic acid (H 2 glyha) ligand with copper( ii ) and lanthanide( iii ) salts in the presence of diamagnetic [Na 2 {Fe(CN) 5 (NO)}] led to two series of isostructural complexes, which can be designated as heterotrimetallic dimeric clusters [{LnCu 5 (glyha) 5 }{Fe(CN) 5 (NO)}(H 2 O) 4 ] 2 x NO 3 y H 2 O ( x = 2, y = 11 for La ( 1 ), x = 2, y = 11 for Pr ( 2 ), and x = 2, y = 11 for Nd ( 3 )) and heterotetrametallic coordination polymers [Na{LnCu 5 (glyha) 5 }{Fe(CN) 5 (NO)} 2 (H 2 O) x y H 2 O] n ( x = 6, y = 4 for Sm ( 4 ), x = 6, y = 0 for Gd ( 5 ), x = 6, y = 4 for Tb ( 6 ), x = 5, y = 5 Dy ( 7 ), and x = 6, y = 4 for Ho ( 8 )). Each molecular structure contains Ln III [15-metallacrown-5] nodes and diamagnetic [Fe(CN) 5 (NO)] 2 linkers. The resulting products demonstrate diversified structural frameworks due to the radius effect of Ln III ions and different bridging fashions of diamagnetic [Fe(CN) 5 (NO)] 2 linkers. An analysis of magnetic susceptibilities reveals that 7 exhibits ferromagnetic coupling between Cu II and Dy III ions and field-induced SMM behavior. Two families of metallacrown complexes have been obtained by one-pot procedure. The different radii of Ln ions and the binding fashions of diamagnetic linkers result in diversified structural frameworks.