Radical-Bridged Ln4 Metallocene Complexes with Strong Magnetic Coupling and a Large Coercive Field

Inducing magnetic coupling between 4f elements is an ongoing challenge. To overcome this formidable difficulty, we incorporate highly delocalized tetrazinyl radicals, which strongly couple with f-block metallocenes to form discrete tetranuclear complexes. Synthesis, structure, and magnetic properties of two tetranuclear [(Cp*(2)Ln)(4)(tz(.))(4)].3(C6H6) (Cp*=pentamethylcyclopentadienyl; tz=1,2,4,5-tetrazine; Ln=Dy, Gd) complexes are reported. An in-depth examination of their magnetic properties through magnetic susceptibility measurements as well as computational studies support a highly sought-after radical-induced giant-spin model. Strong exchange interactions between the Ln(III) ions and tz(.) radicals lead to a strong magnet-like behaviour in this molecular magnet with a large coercive field of 30 kOe.

Automated summary

The study successfully induced magnetic coupling between 4f elements by incorporating highly delocalized tetrazinyl radicals, forming stable tetranuclear complexes. Experimental and computational studies revealed the magnetic properties of these complexes, supporting a radical-induced giant-spin model. Strong exchange interactions between Ln(III) ions and tz(.) radicals led to a strong magnet-like behavior in this molecular magnet with a large coercive field of 30 kOe.