Absolute Absorption Intensity and Dispersion Measurements on Some Organic Liquids in the Infrared

Abstract

The infrared absorption spectra and corresponding dispersion spectra of the following liquids have been measured over the range 4200 to 250 cm−1: cyclo-C5H10, CH3·NO2, CH3·CN, CH2Br2, CH2Cl2, CBrCl3, CCl4, C6H6, C6H5·CH3, C6H5Cl, C6H5Br, C6H5I, and C6F6. The spectra were measured in the absence of solvent and the results are reported as the real and imaginary components of the complex refractive index ( n, k). The experimental technique combines transmission measurements through thin films and attenuated total reflection measurements by a method which has been described previously. The complete spectral and dispersion curves are displayed graphically; the absorption maxima are tabulated as absorption indices ( kmax) and as molar absorption coefficients (εmax). The dispersion extrema ( nmin, nmax) are also listed and the experimental uncertainties in these quantities are evaluated. Provision is made to supply the complete optical constant data on magnetic tape at encoded intervals of 0.5 cm−1.