The Polarized Infrared Spectrum of Potassium Bifluoride at –185°C

Observations on the reflection spectrum of potassium bifluoride have recently been reported [1] which appear to confirm the symmetrical linear structure of the bifluoride ion in this crystal. Some time ago absorption spectra of single crystals of KHF2 using polarized infrared radiation were obtained in this laboratory which both confirm this work and supplement it. Owing to the improved resolution of complex absorption regions which we obtained at low temperatures it seems worthwhile to present these results briefly. The spectrum is possibly unique in the wealth of combination and overtone bands which arise from a crystal of structure so simple that a detailed interpretation may be anticipated.