Infrared Absorption Spectra of Aqueous HF2—, DF2—, and HF

Abstract

Strong infrared absorption bands of KHF2 appear at 1233 cm—1 and 1473 cm—1 in the solid, and are observed at 1206 cm—1 and 1536 cm—1 respectively, in H2O solution. Corresponding values for KDF2 are 888 cm—1 and 1045 cm—1 in the solid, and 873 cm—1 and 1102 cm—1 in D2O solution. In saturated KHF2 and in KHF2 solutions containing excess HF, there appear new, broad absorption bands attributed to polymeric species, e.g., H2F3—. The HF2— ion is observed in concentrated aqueous HF; in addition, there is a strong absorption at 1820 cm—1 which is not shifted in D2O-HF mixtures.