Infrared-Reflection Spectra of Molten Fluoride Solutions: Nb (V) in KF:LiF

Abstract
Infrared‐absorption spectra derived from reflectivity measurements over the range 4000 to 200 cm−1 have been obtained for KF:LiF melts containing Nb (V). The results show two strong bands at 315 and 555 cm−1 and a very sharp medium band at 250 cm−1 superimposed on the former. Comparison of these spectra with well‐characterized solid compounds such as K2NbF7 demonstrate that the NbF7−2 complex ion is the predominant species in these melts. The NbOF63— anion is shown to be the predominant species in melts containing hydrolyzed Nb (V).