In the first article of this volume Samara and Peercy review the theory
of “soft-mode’’ phase transitions and the research on the effects of
hydrostatic pressure of these transitions. Displacive ferroelectric, antiferroelectric,
and antidistortive transitions are given special emphasis.
This article constitutes the first extensive treatment of such transitions
in this publication since that of Kanzig in Volume 4.
The electrical, optical, and structural properties of the elemental and
binary compound semiconductors have been discussed extensively in a
number of articles here. Interest in the more complex tetrahedrally coordinated
semiconducting compounds, e.g., chalcopyrite, often composed
of three or more elements, has been developing recently. The atomic and
band structures of these compounds are reviewed by Miller, MacKinnon,
and Weaire in the second article of this volume.