LIESST effect and cooperativity of a 2-D Hofmann-type compound

2-D Hofmann-type compound [Fe(4-phPY)(2)Ni(CN)(4)]center dot H2O (4-phpy = 4-phenylpyridine) was synthesized and characterized by magnetic susceptibility measurements. The compound exhibited spin-crossover behavior with thermal hysteresis loop and LIESST effect. The activation energy and the tunneling rate constant were estimated as E-a = 773 (cm(-1)) and k(HL)(T -> O) = 4.51 x 10(-6) (s(-1)) for the compound.