Optical constant, molar absorption coefficient, and imaginary molar polarizability spectra of liquid hexane at 25 °C extended to 100 cm −1 and vibrational assignment and absolute integrated intensities between 4000 and 100 cm −1

Abstract

The infrared refractive index, molar absorption coefficient and imaginary polarizability spectra of hexane presented in a previous paper are extended to 100 cm −1. The vibrational assignment and curve fit of the imaginary molar polarizability spectrum of liquid hexane are presented between 4000 and 100 cm −1. A total of 157 peaks are required to fit the imaginary molar polarizability spectrum. An excellent fit was obtained which has an R 2-value equal to 0.9997, the χ 2 is 0.082 cm 6 mol −2 and the RMS error is 0.0033 cm 3 mol −1. Also the area under the experimental spectrum and the fitted spectrum only differ by 0.08%, where the fit is larger. With the aid of ab initio calculations and the gas phase spectrum, the liquid phase fundamentals and integrated intensities have been assigned for most of the infrared active fundamentals, and the dipole moment derivatives with respect to normal coordinates and the transition moments are reported.