Room temperature switching of a neutral molecular iron(II) complex

Abrupt room temperature switching (T-c = 295 K with a 5 K hysteresis) was achieved in a neutral FeII complex based on a 2-(1H-pyrazol-1-yl)-6-(1H-tetrazol-5-yl) pyridine ligand. Structural characterization and spin crossover study (via SQUID magnetometry, photoexcitation and X-ray absorption spectroscopy) in the solid state are described.