Surprises from a Simple Material—The Structure and Properties of Nickel Cyanide

The cyanide switch. The bonding of the cyanide ligand of Ni(CN)2⋅n H2O changes dramatically on dehydration to Ni(CN)2, equalizing the NiC and NiN bonds and switching the Ni2+ ion bound to nitrogen from high spin to low spin. Total neutron diffraction studies on Ni(CN)2 provide for the first time accurate structural data on this simple layered metal cyanide. Ni(CN)2 is a model two-dimensional negative thermal-expansion material. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z701246_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.