This FTIR spectroscopy experiment is designed to provide undergraduate chemistry students with experience in using sampling methods commonly used in industry and research. In the experiment described here the use of modern infrared sampling techniques, DRIFTS (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) and ATR-FTIR (Attenuated Total Reflectance–Fourier Transform Infrared) spectroscopy are used in addition to the traditional transmission mode of infrared spectroscopy. Using these methods, powder and aqueous- phase samples can be analyzed for structural characteristics of water soluble organic ligands. In the experiment, ethylenediaminetetraacetic acid (EDTA) sodium salts are studied as well as the complexation between EDTA and lead ions. Students assign vibrational bands in the spectra, analyze band shifts for evidence of complexation, and learn the differences between transmission and reflectance mode sampling techniques.
Lanigan et al. (Fri,) studied this question.