Assembling into Chiral Crystal of Spin Crossover Iron(II) Complex

A new spin crossover iron(II) complex, [Fe(H2L2-Me)(2)]Cl-2 center dot 2-PrOH center dot 0.5H(2)O (1), has been prepared, where H2L2-Me = (2-methylimidazol-4-yl)methylidene)histamine. The complex is a chiral molecule due to octahedral coordinations of two tridentate ligands, they are linked by the hydrogen bonds of NH center dot center dot center dot Cl-center dot center dot center dot HN through Cl- ion into a chiral one-dimensional (1D) rod, and further the chiral rods with the same chirality are stacked to form a chiral crystal (conglomerate). The solvated sample showed a two-step SCO, and the desolvated sample showed an abrupt one-step SCO at T-1/2 = 180 K.