This volume presents a sequence of articles which describe the
theoretical treat- ments of investigating the fundamental features in
the electronic structures and properties of typical
quasi-one-dimensional solids; organic conductor TTF-TCNQ, polyacetylene,
metallic and superconducting polymer (SN)n and linear chain chal-
cogenides and halides of transition elements including NbSe3' The aim of
this volume is not to present an exhaustive review but rather to touch
on a selective class of problems which appear to be fundamental for
typical quasi-one-dimensional solids. Thus the topics in this volume are
rather confined to the key basic properties of quasi-one-dimensional
systems. The quasi-one-dimensional solids are one of the most
extensively investigated subjects in current physics, chemistry and
materials science. These materials are unique in attracting a broad
range of scientists, chemists, experimental and theore- tical
physicists, materials scientists and engineers. In 1954 Frohlich
constructed a theory of superconductivity based on a one-dimensional
model of moving charge density waves. In 1955 Peierls predicted that
anyone-dimensional metal is unstable against the distortion of a
periodic lattice so that a metal-nonmetal transition occurs at a certain
temperature for a one-dimensional metal. According to these theories a
gap is opened at the Fermi surfaces of one-dimensional conductors at low
tempera- tures and the charge density wave is created in connection with
the occurrence of the gap.