Transition Metal Borides: Superhard versus Ultra‐incompressible

Borides of several heavy transition metals have been synthesized by arc melting at ambient pressure. The materials are characterized by either low compressibility or high hardness, some of them showing a good compromise between both properties. The structure–property relationship is revealed based on their crystal structures and a chemical bonding analysis by means of the electron localization function. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2089/2008/adma200703025_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.