Popis: |
A generation ago scientists at Du Pont's Central Research and Development Department sought to prepare, understand, and exploit organic molecules lacking aliphatic hydrogens and possessing a large cyano group to carbon ratio. Like many other ambitious quests the anticipated goal (of commercializing a new family of polymers) was not realized. Nonetheless, the discoveries made during this pursuit have made a permanent mark on the evolution of science. Most notably, the discovery of tetracyanoethylene (TCNE), and 7,7,8,8-tetracyano-p-quinodimethane (TCNQ), and the remarkable stability of their radical anions led to an unusual series of charge transfer salts. Many of the TCNQ electron-transfer salts exhibit high, metal-like, dc electrical conductivity. These initial observations led to the evolutionary development of conducting polymers and the realization of molecular based ferromagnets. |