OPTICAL-PROPERTIES OF THIN BARIUM FILMS

The optical properties of thin barium films, with various thicknesses, were determined in normal incidence in the energy range 2-5. 6 eV. From the results for the thickest films, the optical constants are determined using a method of successive approximations and are compared with those of other authors; an interpretation is attempted in terms of electronic transitions. The results concerning the thinnest films are explained using the Maxwell-Garnett theory that describes in a satisfactory manner the dependence of the phenomena on the thickness of the films.