The way that photons impart momentum on the surface of a mirror, for example a solar sail.
The negative charge of the electron is greater while it is coherent with the photons, so the acceleration of the sail is actually a result of the magnetic attraction between the nucleus and the electron. In the case of a mirror, the only path for the photon is around the backside of the atom and ejected from the front. Assuming that the photon does not cohere and decohere from the exact same point in the electron orbital, there would necessarily be some segment of the orbital where the electron is weaker, such that there is a net thrust in the direction opposite from that segment.