Photons propagate in a certain direction. When it encounters an atom on its way, and an energy of photon is equal to the energy difference between some levels in the atom photon can be absorbed. But, what happens if an energy of the photon does not match energy difference between levels in the atom. Since atom is "on the way" of photon propagation. How photon will behave in this way? Will the vector of propagation be changed? If yes, on which angle will it deviate? And what makes it to deviate? Or the direction of the photon will stay unchanged?