  We provide a theory for the effects of polarons and phonons in mediating and
suppressing the quantum tunneling of electrons into single molecules of
conducting polymers, motivated by experiments on molecular quantum dots. The
effects of both phonons and excitations of the polaron particle-in-a-box
excitations are calculated. Using both the Su-Schrieffer-Heeger (SSH) model of
polyacetylene and direct density-functional theory (DFT) calculations, we
calculate the suppression of ground--state to ground--state transitions and the
position and strength of the side-bands.
