Far-infrared absorption in nitrous oxide and fluoroform and its molecular interpretation

Abstract

A high pressure cell for spectroscopic studies has been constructed to contain gas at up to 100 b, and to provide a continuously variable sample thickness up to a maximum thickness of 1.4 cm. The far-infrared spectra of nitrous oxide (N₂O) and fluoroform (CHF₃) in the gaseous and liquid phases have been obtained by Fourier spectroscopy using Michelson and lamellar grating interferometers. In the gas phase, the spectral contours and integrated intensities agree well with theoretical calculations. In the liquid state, there is evidence that the N₂O molecules undergo libratory motion, while the CHF₃ molecules show an essentially free rotation.