The first part of this equation is the Rayleigh scattering
(only the frequency of incident light v0 is used). The
second part of (7) represents the Raman scattering, its
Stokes part (v0 – vvib) and anti-Stokes part (v0 + vvib)
respectively – see Fig. 4 and 5. From the second part of (7)
it is obvious that the existence of the Raman scattering
depends on the change of the polarisability ∂α with change
of the distance ∂r.