A family of dodecanuclear Mn(11)Ln single-molecule magnets

作者：Mereacre Valeriu; Lan Yanhua; Wernsdorfer Wolfgang; Anson Christopher E; Powell Annie K^*

来源：Comptes Rendus Chimie, 2012, 15(7): 639-646.

DOI：10.1016/j.crci.2012.05.015

• Manganese
• Lanthanides
• Structure elucidation
• Magnetic properties
• Single-molecule magnets

A series of four isostructural dodecanuclear complexes [Mn(III)9Mn(II)2Ln(III)(0)(8)(OH)(Piv)(16) (NO3)(CH3CN)]center dot xCH(3)CN center dot yC(7)H(16) (piv = pivalate; x = 1/2, y = Ln = Tb (1); x = 2, y = 1/2, Ln = Dy (2), Ho (3), and Y (4)) has been prepared for which the structural motif described as %26apos;a lanthanide ion nested in a large manganese shell%26apos; is observed. All compounds show out-ofphase signals in their ac susceptibilities, and their single-molecule magnet behaviour was confirmed by single-crystal micro-SQUID studies of 1-3 which show hysteresis loops of molecular origin at T %26lt; 1.0 K. The SMM behaviour observed in compounds 1-3 is more pronounced than that for 4, which contains the diamagnetic Yu(III) ion. This is principally the result of ferromagnetic coupling between the paramagnetic anisotropic Le(III) ions (Tb-III. Dy-III and Hot(III)) and the manganese shell, which enhances the total spin ground state of the complexes.

• 出版日期2012-7