Berreman Effect in IR Spectra of Ultrathin Films

Identification of Berreman Effect in IR Spectra of Ultrathin Films 

The first practical problem in the interpretation of experimental IR spectra of a layered structure [particularly for nonmetallic supports and relatively thick films d 100 nm) on metals] is to distinguish between Ihe v xo and vlo bands. In the following, practical solutions to this problem will be presented. 

The most rigorous approach is to generate spectral simulations using the exact Fresnel formulas (Sections 1.5-1.7) however, this requires a knowledge of the optical constants of the film over the spectral range of interest. Special methods may be used to measure the optical parameters of thin films in their final form (Sections 3.10 and 3.11). To simplify the problem, differences between the optical 

The following experimental techniques can be employed for the evaluation of Vlo of the film, depending on the accuracy required and the resources available [45, 47]  

Direct determination from the band maxima in IRRAS of ultrathin films 

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