Regulating Spin-State Switching by Integrating Polyoxometalate Anion into Spin Crossover System.

Polyoxometalate (POM) anions were successfully integrated into Fe(II) spin crossover (SCO) system, which demonstrates an effective role in regulating spin-state switching properties. Specifically, three drastically different magnetic behaviors of Fe(II) ion in the identical cation [Fe(bpp) 2 ] 2+ were achieved by leveraging [Mo 6 O 19 ] 2- , [Mo 8 O 26 ] 4- , and [Na(Mo 8 O 26 )] 3- , respectively.