A NOVEL TECHNIQUE FOR RECORDING INFRARED-SPECTRA OF POWDERS - ATTENUATED TOTAL-REFLECTION IMMERSION MEDIUM SPECTROSCOPY

A new recording technique for the measurement of infrared spectra of p owders using ATR spectroscopy is presented in this paper. The method, called ATRIMS (attenuated total reflection immersion medium spectrosco py), circumvents some ofthe problems of conventional methods. With ATR IMS, an ATR reflection element is covered with a thin film of liquid p araffin (Nujol) as an immersion medium for the powder. Compared to ATR spectroscopy of dry powders on the surface of a reflection element, A TRIMS shows higher band intensities, lower detection limits, reduced n ecessary sample amount, easier handling, and shorter analysis time. Th e resulting spectra have the typical band intensity-wavelength relatio nship of ATR spectra. The method is well suited for the investigation of strong absorbing substances (e.g. magnetite) and strong scattering substances (e.g. hydrargillite).