We discuss situations where thermogravimetric/Fourier transform infrared (TG/FT-IR) plots are obtained which differ substantially from the expected ones. The most common of these situations involves samples that release atmospheric components (H<sub>2</sub>O, CO<sub>2</sub>) at low temperatures. It is shown that the phenomena are mainly related to the purging action of the carrier gas, which strongly influences the spectroscopic portion of the TG/FT-IR plot. Such an influence, as well as the different situations originating from it, is discussed and explained on the basis of an analogy with the operational mode of a conventional dispersive spectrometer.
A. Marini, V. Berbenni, D. Capsoni, R. Riccardi, and T. Zerlia, "Factors Affecting the Spectral Response in a TG/FT-IR Experiment," Appl. Spectrosc. 48, 1468-1471 (1994)