Single-Molecule Magnets: Different Rates of Resonant Magnetization Tunneling in Mn12 Complexes

Two new molecular magnets , the dodecanuclear manganese complexes of the type [Mn₁₂O₁₂(O₂CR)₁₆(H₂O)₄] (known for R = CH₃, new for R = o-ClC₆H₄, o-BrC₆H₄) have contributed to a better quantum mechanical understanding of single-molecule magnets. For instance, appreciable differences in the steps seen in the magnetization hysteresis loops of these high-spin clusters are attributed to changes in the rates of magnetization tunneling from one complex to another.