Hexanuclear [Cp*Dy]6 single-molecule magnet†
Abstract
A hexanuclear cluster [(Cp*Dy)6K4Cl16(THF)6], [Cp*Dy]6, has been constructed from six {Cp*DyIII} synthons in which the strongly coordinating Cp*− caps determine the local anisotropy axes. Structural characterization of [Cp*Dy]6 shows two almost parallel triangular (Cp*Dy)3 fragments that are linked by the K+ and Cl− ions. Magnetic measurements reveal slow thermal relaxation and fast quantum tunneling relaxation in the absence of an external dc field. After applying a weak dc field, the quantum tunneling relaxation is efficiently suppressed, giving a sizable energy barrier of 561 K, which represents the current record energy barrier for high nuclearity organometallic SMMs.