title: Application of thin-film interference coatings in infrared reflection spectroscopy of organic samples in contact with thin metal films.
abstract: A thin dielectric IR-transparent interlayer is introduced between an IR-transparent medium of incidence and a thin metal film. The interlayer increases the intensity of light on the metal/sample interface at certain wavenumbers. By computations, the reflectivities of the system "calcium fluoride (CaF)-germanium (Ge)-gold (Au) sample" are analyzed as a function of incidence angle and Ge layer thickness. Absorbance spectra with acetonitrile as a sample are recorded for different angles of incidence and polarizations and compared to computations. A characteristic feature of the absorbance spectra is the occurrence of interference fringes distributed between 1000 and 6000 cm(-1), i.e., over the complete mid-IR wavelength range into the near-IR. These fringes could be used in analytical spectroscopy.
authors: Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany. m.reithmeier@mpie.de
authors: Martina
authors: M
authors: Reithmeier
authors: Andreas
authors: A
authors: Erbe