(Above) Room Temperature Fe(II) Spin Transition

Several recent publications of our group report on the temperature-driven switching between a diamagnetic Fe(II) low spin and the paramagnetic high spin states. Conceptually, room temperature switching was achieved by the surpamolecular linking of mononuclear Fe(II) spin transition centres via hydrogen-bonding, coordination bonding or halogen-halogen contact. These results set the base for using of the spin transition phenomenon in molecular device applications.

Scheme showing the bispyrazolyl-pyridine ligand based construction design of 1D Fe(II) spin transition chains (top) exhibiting room temperature spin state switching (bottom).