Infrared dispersion of liquid triethylamine

The spectra of the real and imaginary components of the complex refractive index were determined from thin film transmission studies of liquid triethylamine (TEA) using a new method, which takes into account the dispersion of the refractive index in the visible range and integration over the entire NIR, IR and FIR absorption range. From these data the spectra of both components of the complex electric permittivity and complex polarizability of liquid TEA were determined in a broad optical range (25 000–150 cm−1). Related high-frequency dielectric properties, especially the molar vibrational polarization of the liquid related to various spectral ranges has been determined and discussed. It has been found to be extremely small for overtone bands. The main contribution stems from the region of deformation modes of the molecule.