Single-chain magnets: beyond the Glauber model

Single-chain magnets (SCMs) are one-dimensional (1D) slow-relaxing magnetic chains with interesting fundamental properties and applications, such as information storage. The mechanism underlying the slow relaxation of SCMs is Glauber dynamics, in which R. J. Glauber proposed about 50 years ago that the 1D correlation of ferromagnetically coupled Ising spins causes very slow magnetic relaxation at a finite temperature. Since the first experimental observation of SCM dynamics of a cobalt(II)–organic radical alternating chain in 2001, several SCM systems have been reported, supporting and expanding the Glauber model. In this review, we present the recent advances concerning SCMs with the main focus on SCM systems beyond the Ising limit, SCMs constructed with non-collinear or canted antiferromagnetic intrachain interactions, the relation between SCM dynamics and interchain interactions, and some SCMs with chirality, porosity, spin-crossover, photo-switchable states, and so on.