PROTOTYPE STRUCTURES FOR AMORPHOUS SEMICONDUCTORS.

Some of the canonical versions of topologically disordered structures include molecular, polymeric and network glasses. Among the amorphous semiconductors are examples of each which have been sufficiently refined through direct measurement of the radial density function combined with modelling studies and through inference from the vibrational and electronic properties, to serve as prototypes. Evidence for this type of detailed characterization is drawn particularly from amorphous Si or Ge, group IV alloys, and the III-V compounds. Three-fold coordinated As and its structural analogues are also discussed along with some chalcogenides (VI) and some V-VI and IV-VI alloys.