Magnetism‐Structures Relationship of 3,5‐Heptanedione Dy(III) SMMs Based on the Nitrogen‐Containing Auxiliary Ligand

Two new 3, 5‐heptanedione ( β ‐diketonate) dysprosium complexes, namely, [Dy(L) 3 (phen)] ( 1 ) and [Dy(L) 3 (tmphen)] ( 2 ), have been designed and isolated by reactions of 3, 5‐heptanedione with dysprosium chloride and auxiliary ligand under room temperature (L=3, 5‐heptanedione, phen=1, 10‐phenanthroline, tmphen=3, 4, 7, 8‐tetramethyl‐1, 10‐phenanthroline). X‐ray crystallographic analysis reveals that complexes 1 and 2 are mononuclear, and the Dy(III) ions are eight coordinated forming the square‐anti‐prismatic geometry. Complexes 1 and 2 were characterized by various means including elemental analysis, IR and UV spectroscopy. Magnetic studies indicate that both complexes 1 and 2 are single‐molecule magnets (SMMs) under zero dc field. Notably, the auxiliary ligand plays an essential role in regulating their magnetism, which result in the essential magnetism difference between complexes 1 and 2 .