Experimental Method for Investigation of Rotational Spectra of Heavy Molecules at Their Interaction with the Microwave Field at Frequencies of 2–4 GHz

Abstract

An experimental setup based on a powerful ultrawideband microwave source is devised to investigate absorption spectra of gaseous substances. A technique is developed for measuring the absorption coefficient of a substance. It is based on detection of a change in the spectrum of microwave radiation on its passing through the substance under study and is therefore low sensitive to features of the incident radiation spectrum. The accuracy is further increased by multiple repetition of measurements. Rotational spectra of organofluorine compound C₄F₉I vapor are investigated. In the spectral range under consideration, a number of microwave radiation absorption peaks are observed in this compound.