A generalized Chudley-Elliott vibration-jump model in activated atom   surface diffusion
  Here the authors provide a generalized Chudley-Elliott expression for activated atom surface diffusion which takes into account the coupling between both low-frequency vibrational motion (namely, the frustrated translational modes) and diffusion. This expression is derived within the Gaussian approximation framework for the intermediate scattering function at low coverage. Moreover, inelastic contributions (arising from creation and annihilation processes) to the full width at half maximum of the quasi-elastic peak are also obtained. 
R. Martinez-Casado, J. L. Vega, A. S. Sanz, and S. Miret-Artes