Toward heterometallic single-molecule magnets: Synthetic strategy, structures and properties of 3d-4f discrete complexes

3d-4f heterometallic discrete complexes have enjoyed increasing attraction in recent decades because of their potential advantages to create new single-molecule magnets: the moderate magnetic couplings between 3d and 4f spin carriers and significant single-ion magnetic anisotropies of 4f ions. Herein we review the synthetic strategy, structures and magnetic properties of 3d-4f discrete complexes. Particular attention is paid in this review to the examples showing dynamics of the magnetization.