In recent years the coupling of two or more analytical techniques to take advantage of their individual benefits has become quite popular. Among these resultant tools is gas chromatography-infrared spectroscopy (GC-IR). In this merger the separation capability of gas chromatography is paired with the identification advantages of the infrared technique. In order to utilize fully the comparative value of infrared in the qualitative identification of GC effluents, a spectral collection of compounds in the vapor phase is necessary. The vast majority of reference spectra presently available are of the condensed phases with only a couple of compilations treating the vapor phase separately. The infrared spectra of compounds in the gaseous state at elevated temperatures are often considerably different than those taken of the same compounds in the condensed phases at ambient temperatures due primarily to intermolecular interactions that occur in the condensed states. Therefore, comparison of spectra between the gaseous and liquid or solid states can be very misleading. In order to fill the need for an infrared spectra collection for use in identifying GC effluents, Sadtler has recently introduced a continuing vapor phase spectra compendium.
M. J. Flanagan, "A Convenient Sampling Technique for Infrared Vapor Phase Spectra of Liquid and Solid Samples," Appl. Spectrosc. 34, 87-88 (1980)