Electronic transport through a local state linearly coupled to phonon   modes
  A resolvent formalism is applied to the problem of inelastic scattering of an electron linearly coupled to a set of phonon modes. It is shown how the many phonon mode coupling and excitation can be reduced to a single phonon mode description, consistent with other approaches to the phenomenon of inelastic tunneling in heterostructures. A unifying connection is made with the phenomena of resonant electron scattering through molecules in the gas phase and of tunneling of electrons through adsorbates in scanning tunneling microscopy. 
M. A. Gata