Periodic lattice distortions and charge density waves in one- and two-dimensional metals

At low temperatures, low dimensional metals are commonly found to exhibit superlattices incommensurate with the primitive lattice (periodic lattice distortion coupled to charge density waves, PLD — CDW). Transitions to such states are driven by strong electron phonon coupling and favoured by the particular forms of the Fermi surfaces of these metals. Experimental investigations of the structural distortions, and of the changes in electronic structure around the Fermi level produced by the CDW — PLD state, will be discussed for the layered dichalcogenides, the linear chain platinum complex KCP, and the organic charge transfer salts.