Advances in polynuclear iron(II), iron(III) and cobalt(II) spin-crossover compounds

This review describes the recent advances made in the syntheses, structures (including the use of synchrotron sources and variable-temperature crystal structures and PXRD determinations of unit cell axes), magnetism, and photomagnetism of dinuclear and 1-D chain spin-crossover compounds of (primarily) iron(II), iron(III) and cobalt(II). It focuses on the work of the author's group and also includes a discussion of related work by other groups. In particular, the early and ongoing work by Kahn, Real, Gutlich and co-workers on bipyrimidine-bridged Fe-II dinuclear materials has been extended by us and others to include many other new bridging and cappingligands. This had led to a fuller understanding of the spin transitions that involve HS-HS, HS-LS and LS-LS pair states. The same is being achieved for new 1-D chain materials, and notable advances include structural observation of ordered and disordered metal centres and corresponding spin states. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).