https://doi.org/10.1351/goldbook.08673
Reflection-absorption with very thin layers of an absorbing material on a metallic substrate and the angle of incidence between \(\pu{70\!^{\circ}}\) and \(\pu{90\!^{\circ}}\).
Note: As the incident radiation beam travels nearly parallel to the sample surface, the electric vector of the radiation is then either parallel or nearly perpendicular to the surface.