Abstract
Non-equilibrium molecular dynamics is used to investigate the energy transport in both disordered and anharmonic linear chains under thermal stress by analysing the contribution to thermal flow of the vibrational normal modes. A thermal balance of the normal-mode energy is built up by considering the anharmonic interaction and the coupling with the reservoirs. The non-equilibrium normal-mode dynamics is studied and it is shown that, for both harmonic and anharmonic systems, the steady-state lattice thermal conductivity is described by a set of stationary normal modes with broadened and overlapping Fourier spectra. The origin of the thermal gradient is discussed. Because of the small number of atoms the bulk conductivity cannot be established.