Magnetic Relaxation in Lanthanide Containing Complexes

1 Single-Molecule Magnets Including Lanthanide Ions 

8 K and from 50 to 10 000 Hz, and a semicircle was found, which indicates a single relaxation process. Another increment of xm and xm is found below 6 K, and this type of increment is also found in other systems [107-109], It is suggested that intermolecular interactions in such low temperature regions may give rise to the phenomena. 

The above examples are SMMs of the 3d f series. In some of the 3d f SMMs, the major anisotropy comes from the 3d ions, such as Mn +, Co + or Fe + [111, 112]. There are some pure 4f clusters that behave as SMMs [115,116]. Powell and coworkers reported two pure lanthanide SMMs in 2006 [116], both of which are dysprosium clusters and they share a similar 

1 Single-Chain Magnet Including Lanthanide Ions 

The first reported SCM using rare earth ions as the anisotropic source was (LCu)2Tb(N03) [121], where H3L = 2-hydroxy-A- 2-[(2-hydroxyethyl) amino] ethyl benzamide). The frequency dependency of the xm is observed below 5K for frequencies ranging from 1 to 1000 Hz. Through Arrhenius analysis the energy barrier is calculated to be 28.5 K and relaxation time constant is 3.8 x 10 s. It should be noted that these workers failed to obtain the crystal structure of the compound and the formula was determined based on elemental analysis. 

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