Introduction Click to copy section linkSection link copied! Slow magnetic relaxation of molecular origin stems from the presence of a bistable magnetic ground state with an effective energy barrier to spin inversion (Ueff) in paramagnetic complexes. (1) In the absence of fast quantum tunneling, such single-molecule magnets (SMMs) exhibit magnetic memory effect, which is experimentally captured as open magnetic hysteresis loops, a property highly coveted for potential high-end applications.