Total external reflection Bragg diffraction

In the case of thin films or monolayers, two different techniques can be employed these are the total external-reflection Bragg diffraction (TERBD) technique introduced by Eisenberger and Marra and the previously mentioned technique based on crystal truncation rods, introduced by Robinson, which can provide in-plane structural information or information on interfacial roughness, respectively. 

Marra, W.C., Eisenberger, R, and Cho, A.Y., X-ray total-external-reflection-Bragg diffraction A structural study of the GaAs-Al interface, J. Appl. Phys., 50, 6927,1979. 

This technique (sometimes referred to as grazing incidence x-ray scattering) essentially involves conventional Bragg diffraction under conditions of total external reflection. 

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