The Attenuated Total Reflection (ATR) method has shown to be a powerful tool for optical characterization of metal surfaces /1/. The effect of a double interface /2/ and the modification of surface electromagnetic waves (SEW) by very thin layers /3/ have also been studied using this technique.
L. E. Regalado,
"A New Parameter In The ATR Technique For Optical Constants Determination", Proc. SPIE 0813, Optics and the Information Age, (1 January 1987); doi: 10.1117/12.967231; https://doi.org/10.1117/12.967231