Matrix Effects in Matrix Isolation Infrared Spectroscopy

A major factor limiting extensive use of matrix isolation gas chromatography-Fourier transform infrared spectrometry is the incompatibility of matrix-isolated spectra with available vapor- or condensed-phase spectral data bases. Here, matrix and surface effects on matrix isolation infrared spectra of organic molecules are investigated. Use of xenon at −215°C (58 K) to obtain matrix isolation spectra that are similar to condensed-phase spectra is demonstrated. Finally, the effect of temperature on reflection-absorption infrared spectra of matrix-isolated molecules is discussed, and guidelines for obtaining and interpreting matrix isolation infrared spectra of gas chromatographic eluants using the existing condensed phase data bases are provided.