An Organometallic Sandwich Lanthanide Single-Ion Magnet with an Unusual Multiple Relaxation Mechanism

A dysprosium(III) sandwich complex, [Dy-III(COT '')(2)Li(THE)(DME)], was synthesized using 1,4-bis(trimethylsilyl)cyclooctatetraenyl dianion (COT ''). The complex behaves as a single-ion magnet and demonstrates unusual multiple relaxation modes. The observed relaxation pathways strongly depend on the applied static dc fields.