In a recent work, we provided a standardized and exact analytical
formalism for computing in the semiclassical and asymptotic regime,
the radiation force experienced by a two-level atom interacting with
any number of plane waves with arbitrary intensities, frequencies,
phases, and propagation directions [J. Opt. Soc. Am. B
35, 127 (2018)JOBPDE0740-322410.1364/JOSAB.35.000127].
Here, we extend this treatment to the multilevel atom case, where
degeneracy of the atomic levels is considered and polarization of
light enters into play. A matrix formalism is developed to this
aim.