A Mixed 3d-4f 14-Metallacrown-5 Complex That Displays Slow Magnetic Relaxation through Geometric Control of Magnetoanisotropy

作者：Boron Thaddeus T III; Kampf Jeff W; Pecoraro Vincent L^*

来源：Inorganic Chemistry, 2010, 49(20): 9104-9106.

DOI：10.1021/ic101121d

We describe the synthesis and magnetic properties of a unique mixed 3d-4f 14-metallacrown-5 complex. This is the first metallacrown family to feature mu-O and mu-OH bridges as well as to incorporate a Ln(lll) ion into the ring. Alternating-current SQUID magnetometry of the Tb, Dy, and Ho derivatives reveals slow magnetic relaxation, a hallmark property of single-molecule magnets. For the Dy structure (4), an effective energy barrier U(eff) of 16.7 K and a relaxation time of 4.9 x 10(-8) s were calculated. Because of the relatively small total spin, this behavior most likely results from a large magnetoanisotropy, which is controlled through geometric constraints.

• 出版日期2010-10-18