The infrared spectra of seven phenylchlorosilanes have been measured from 2 to 30 microns The spectra of certain phenylchlorosilanes are very similar in the 2-15 micron wavelength region but show marked differences in the 15-30 micron range, where there are Si-Cl stretching and aromatic-ring deformation vibrations. Based on these differences, methods for the quantitative analysis of mixtures of phenylchlorosilanes have been developed using a double-beam, double-pass spectrometer equipped with a CsBr prism and a new, low-cost KBr spectrometer With double-beam compensation, low concentrations of phenyltrichlorosilane in diphenyldichlorosilane can be determined Techniques for the quantitative analysis of mixtures of phenyltrichlorosilane, diphenyldichlorosilane, and chlorobenzene are described. Because atmospheric water vapor absorbs strongly in the CsBr region, flushing the spectrometer with dry air or nitrogen improves the accuracy of absorbance measurements.
Maurice E. Grenoble and Philip J. Launer, "Infrared Analysis of Phenylchlorosilanes in the CsBr Region," Appl. Spectrosc. 14, 85-90 (1960)