Spin transition in a chainlike supramolecular iron(II) complex

A one-dimensional supramolecular head-to-tail N+-H center dot center dot center dot N-type hydrogen-bonded chain of the complex [Fe-II(L)(2)H](ClO4)(3)center dot MeOH [L = 4'-(4'''- pyridyl)-1,2':6'1''-bis(pyrazolyl)pyridine] exhibits a reversible, thermally driven spin transition at 286 K with a hysteresis loop of ca. 2 K.