Abstract
Metal Organic Frameworks (MOFs) are a very prominent research topic because of their potential uses in applications such as molecular devices, gas storage systems, and especially single chain magnet (SCM) materials. Among these MOFs, those that feature open metal sites (Ni2+) inherently possess spin states that are tunable via organic molecular coordination. They have demonstrated the potential of SCM materials, exhibiting the possibilities for the spin-canting, magnetic phase transition, and field-induced spin slow dynamics behavior.
In this paper, we experimentally and theoretically investigated the magnetic properties of a MOF possessing an open metal site, and its derivatives. It exhibits a magnetic ordered state at low temperatures, which can be altered by altering its imidazole (IM) coordination. Our results show that coordinated IM clearly influences the spin state of Ni(II) ions with orbital geometries, resulting in shifts in critical temperature and field. These obtained results imply that the magnetic behavior in MOFs with IM reveals the coexistence of spin-canting, metamagnetism, magnetic phase transitions, and field-induced spin slow dynamics.
To the best of our knowledge, this is the first example of a MOF exhibiting the influence of the spin state of Ni(II) ions with orbital geometries via organic molecular coordination, which shows the coexistence of spin-canting, metamagnetism, magnetic phase transition, and field-induced spin slow dynamics.