A series of Au and Ag films was deposited on the Dove prisms with different
refractive indices. By this solid-contacting configuration, it was found t
hat the spectra of dielectric function measured at the metal-substrate inte
rface do change with the refractive index and differ from those measured at
the metal-air interface in both the Drude and interband transition regions
. This phenomenon may be explained by the surface optical properties of the
noble metals , which will strongly depend on the ambient. The reconstructi
on of the surface state related to the different medium may account for the
effect that should be taken into consideration in the optical and magneto-
optical applications involving metallic multilayer film structure design.