The evolution of the ν HF band of weak HCN…HF, CH 3CN…HF complexes on transition from gas to liquid state

Abstract

The evolution of the ν HF band shape in the infrared spectra of HF/Xe and HF/HCN/Xe, CH 3CN/HF/Xe mixtures has been studied on transition from gas to liquid phase. The fine structure of the ν HF bands of HCN…HF, CH 3CN…HF complexes disappears gradually with Xe density increase up to γ=20 or γ=10 amagat, respectively. With further increase of Xe density up to 300 amagat the structureless ν HF complex band in the spectra of both mixtures shifts gradually to lower frequencies and becomes more symmetric; its M * 2 spectral moment increases. The appearance of a Q branch of the ν HF band in the spectra of HF/Xe gaseous mixtures is assigned to formation of Xe…HF complexes.