MECHANISM OF SHEAR-INDUCED METALLIZATION

It is well-known that volumetric compression converts insulators into metals (the Herzfeld-Mott transition). Not so well-known is the fact that finite shear strains have a similar effect. For example, uniaxial compression of Si and Ge causes them to become metallic. A simple band-structure model for this is presented in this paper. Shear induced metallization has several important consequences, including: mechanically induced phase transformations, other mechanochemistry; the hardnesses of semiconductors and carbides; and ultra-fast reactions at detonation fronts.