There is no doubt that in the development of the Physics and Chemistry
of Solids during the last fifteen years, the very important place taken
by low-dimensional compounds will be remembered as a major event.
Dealing very widely at the beginning with two-dimensional structures and
intercalation chemistry, this theme progressively evolved as the
synthesis of one-dimensional conductors increased, along with the
observation of their remarkable properties. Beyond the classical
separation of the traditional disciplines, essential progress has
stemmed each time from the concerted efforts of, and overlapping
between, chemists, experimental physicists, and theoreticians. This book
is a synthetic approach which aims to retrace these united efforts. The
observation and characterization of charge density waves in their static
or dynamic aspects have been the main points to attract the interest of
researchers. Two broad categories of compounds have been the material
basis of these observa- tions: transition-metal polychalcogenides and
either condensed-cluster phases or bronze-type compounds. These families
are referred to throughout the various chapters of this book, thus
illustrating the continuous progress of concepts in this domain and, at
the same time, providing the first synthetic and exhaustive view of this
group of materials.