INFRARED INTENSITIES OF LIQUIDS XXII - OPTICAL AND DIELECTRIC-CONSTANTS, MOLAR POLARIZABILITIES, AND INTEGRATED-INTENSITIES OF LIQUID BENZENE-D(6) AT 25-DEGREES-C BETWEEN 5000 AND 450 CM(-1)

This paper presents accurate infrared absorption intensities of liquid benzene-d(6) at 25 degrees C, between 5000 and 450 cm(-1). The result s are presented as graphs and tables of the real, n, and imaginary, Ic , refractive index spectra, which are also called the optical constant spectra. The real refractive index is shown between 8000 and 450 cm(- 1). The absolute errors in the k values are estimated to be similar to 3% below, and up to 60%, above 4700 cm(-1), with those in the n value s similar to 0.25% throughout. The Beer-Lambert molar absorption coeff icient spectra, E-m((v) over tilde), and the complex dielectric consta nt spectra, epsilon'((v) over tilde) and epsilon ''((v) over tilde), w ere calculated from the optical constant spectra. To correct for macro scopic dielectric effects, the complex molar polarizability spectra, a lpha(m)' and alpha(m)''((v) over tilde), were calculated from the diel ectric constant spectra under the Lorentz local field. The properties of bands in these different spectra are compared. The imaginary molar polarizability spectra were fitted convincingly to 208 Classical Dampe d Harmonic Oscillator bands, and the areas under the corresponding (v) over tilde alpha(m)'' bands gave the integrated intensities C-j. Thes e were assigned as far as possible and are tabulated. The transition d ipole moments of well assigned transitions, and for the infrared-activ e fundamentals, under the double harmonic approximation, the dipole mo ment derivatives with respect to the normal coordinates, were calculat ed from the values of C-j, and are presented. This appears to be the f irst extensive measurement of the infrared absorption intensities of l iquid benzene-d(6). The results are compared with Literature data for liquid and gaseous benzene-d(6).