Spin-Crossover and Slow Magnetic Relaxation Behavior in Hexachlororhenate(IV) Salts of Mn(III) Complexes [Mn(5-Hal-sal 2 323)] 2 [ReCl 6 ] (Hal = Cl, Br).

The cationic complexes of Mn(III) with the 5-Hal-sal 2 323 (Hal = Cl, Br) ligands and a paramagnetic doubly charged counterion [ReCl 6 ] 2- have been synthesized: [Mn(5-Cl-sal 2 323)] 2 [ReCl 6 ] ( 1 ) and [Mn(5-Br-sal 2 323)] 2 [ReCl 6 ] ( 2 ). Their crystal structures and magnetic properties have been studied. These isostructural two-component ionic compounds show a thermally induced spin transition at high temperature associated with the cationic subsystem and a field-induced slow magnetic relaxation of magnetization at cryogenic temperature, associated with the anionic subsystem. The compounds are the first examples of the coexistence of spin crossover and field-induced slow magnetic relaxation in the family of known [Mn III (sal 2 323)] cationic complexes with various counterions.