  An interaction of electromagnetic S-wave with thin flat metallic film is
numerically studied for the quantum degenerate electron plasma. One considers
the reflectance, transmittance and absorptance power coefficients. A
contribution of quantum wave properties of electrons to the power coefficients
is shown in comparison of the coefficients with ones evaluated for both the
classical spatial dispersion and the Drude - Lorentz approaches. This
contribution is detected for the infrared and terahertz frequencies in case of
nanoscale film width.
