A time-dependent Landau theory is proposed for the transition-metal dichalcogenides coupling the motion of the charge-density waves to the electron liquid. The dissipative terms are related to the metallic resistance. The "phason" or "phonon" excitations of the charge-density wave are found to be overdamped. Resistive anomalies are predicted in the normal state.

• Received 12 February 1975

DOI:https://doi.org/10.1103/PhysRevB.12.1197