Synthesis and characterisation of iron(II) spin-crossover complexes/Molecular Magnetism

Special emphasis is given on synthesis of mono- and polynuclear iron(II) spin crossover compounds and the characterisation of the spin transition behaviour using variable temperature mid and far FT-IR spectroscopy, as it is a rapid method of elucidating the changing in binding properties of the metal-ligand bonds (i.e. the population and depopulation of the anti-bonding eg orbitals).

Recent Work

  • "Fascinating Variabilty in Chemistry and Properties of 2,6-bis-(benzimidazol-2-yl)-pyridine and 2,6-bis-(benzthiazol-2-yl)-pyridine and their Complexes"
    Miroslav Boca, Reginald Jameson and Wolfgang Linert, Coord. Chem. Rev. 255 (2011) 290–317.
  • "A Cu(II)Ni(II) Complex with Ethylenediamine: Crystal Structure and Ferromagnetic behaviour of an Aqua-bridged Heterometallic Chain containing Ambidentate Ni(OAc)42– Blocks"
    Oksana V. Nesterova, Svitlana R. Petrusenko, Dmytro S. Nesterov, Vladimir N. Kokozay, Brian W. Skelton, Julia Jezierska, Wolfgang Linert and Andrew Ozarowski, Eur. J. Inorg. Chem., 22 (2010) 3529 - 3535.
  • "Spin Crossover – an Unusual Chemical Equilibrium"
    Andrei B. Koudriavtsev, W. Linert, J. Struct. Chem, 51 (2010) 335-365
  • "Anion, solvent and time dependence of a 3D coordination polymer exhibting High Spin-Low Spin interactions"
    Guy N. L. Jameson, Franz Werner, Matthias Bartel, Alina Absmeier, Michael Reissner, Jonathan A. Kitchen, Sally Brooker, Andrea Caneschi, Chiara Carbonera, Jean-François Létard and Wolfgang Linert Eur. J. Inorg. Chem. 29 (2009) 3948–3959.

Crystal structure and schematic picture of the 3D network produced by [Fe(4ditz)3(PF6)2].solv. The disordered solvent (red ovals) is statistically distributed in cavities formed between iron atoms of different interpenetrating networks.

Crystal structure and schematic picture of the 3D network produced by [Fe(4ditz)3(PF6)2].solv. The disordered solvent (red ovals) is statistically distributed in cavities formed between iron atoms of different interpenetrating networks.


Contoured solvent difference Fourier synthesis parallel to (001) centered at x,y,z = 0,0,1/2. (A) for methanolate and (B) for ethanolate obtained form synchrotron X-ray difracton. The peripheral difference density peaks between pairs of C3 atoms are due to C-C bond electrons.

Contoured solvent difference Fourier synthesis parallel to (001) centered at x,y,z = 0,0,1/2. (A) for methanolate and (B) for ethanolate obtained form synchrotron X-ray difracton. The peripheral difference density peaks between pairs of C3 atoms are due to C-C bond electrons.


Diagram to illustrate the solvent molecules in all six possible positions in order to show clearly the different rotational properties of (A) methanol and (B) ethanol. Upper figures are capped stick (the red lines do not infer bonds representations, and the lower are space filling diagrams. In both representations, the grey spheres are carbon atoms, the red spheres are oxygen, the blue spheres are nitrogen, the white spheres are hydrogen, and the yellow spheres are fluorine. All views are down the c-axis

Diagram to illustrate the solvent molecules in all six possible positions in order to show clearly the different rotational properties of (A) methanol and (B) ethanol. Upper figures are capped stick (the red lines do not infer bonds representations, and the lower are space filling diagrams. In both representations, the grey spheres are carbon atoms, the red spheres are oxygen, the blue spheres are nitrogen, the white spheres are hydrogen, and the yellow spheres are fluorine. All views are down the c-axis


The characterisation of physical properties is performed in collaboration with Prof. Kurt Mereiter (X-ray structure analysis), Prof. Günther Wiesinger (57Fe-Mössbauer spectroscopy) and Prof. Gerfried Hilscher (magnetic susceptibility measurements - SQUID) within the TU Vienna. Ongoing research focuses on the synthesis of novel 3D coordination polymers and polymeric materials containing spin-crossover iron(II) complexes. This work was funded by the EU-TMR-program TOSS ("Thermal and Optical Spin State Switching") and the ESF program "Molecular Magnets".

Our international main research partners within this project are (among others):

  • Prof. A. Bousseksou, CNRS, Lab. de Chimie de Coordination, Toulouse, France
  • Prof. A. Caneschi, LAboratory for Molecular Magnetism (LA.M.M.) Dipartimento di Chimica e UdR INSTM di Firenze, Italy
  • Prof. A.B. Koudriavtsev, Meneleev Insitute Moscow, Russia
  • Prof. M. Hasegawa, Aoyama Gakuin University. Tokyo, Japan
  • Prof. R. Boca, TU-Bratislava, Slovakia
  • Prof. M. Verdaguer, Laboratoire de Chimie Inorganique et Materiaux Moleculaires, Université Pierre et Marie Curie, Paris, France