Fe[5NO2-sal-N(1,4,7,10)]: a new iron(II) complex exhibiting an unusual two-step spin conversion afforded by a hexadentate ligand with a N4O2 donor set

Abstract The new Fe[5NO 2 -sal-N(1,4,7,10)] spin-crossover complex has been investigated by Mossbauer spectroscopy, magnetic susceptibility measurements, and X-ray diffraction powder studies as a function of temperature. The spin conversion occurs in two steps separated by a 30° broad spin equilibrium domain involving 50% of HS and LS complex molecules. A single structural phase characterizes this complex from 300 to 90 K. This is the first iron (II) spin-crossover complex including a N 4 O 2 donor set.