Einstein Model vs Debye model.

by PsychonautQQ
Tags: debye, einstein, model
 P: 306 In the Einstein model, atoms are treated as independent oscillators. The Debye model on the other hand, treats atoms as coupled oscillators vibrating collectively. However, the collective modes are regarded here as independent. What is the meaning of this independence and how does it contrast with the Einstein model?
 Sci Advisor P: 3,376 The independence of the oscillators is a consequence of the assumed harmonicity of the oscillators, i.e. the forces being linear functions of the displacements. Once anharmonic terms are considered, these will give rise to scattering of oscillations on each other which is among others one reason for the limited thermal conductivity of solids.
 P: 306 you mean in the Einstein model the independence is a consequence of assumed harmonicity of oscillators? Or in the Debye model the collective modes are regarded as independent because of the assumed harmonicity?