Brief review of molten fluoride systems

Fluoride systems containing aluminum trifluoride, AIF3, were investigated in greater detail. Based on Raman spectra, researchers repeatedly demonstrated the presence of two types of complex ions, AIF4 and A1F63 [347 — 350]. The spectral parameters of these complexes are as follows (wave numbers in cm 1)  

Bates and Boyd investigated Raman spectra of the molten systems NaF - LiF - BeF2 [351] and NaBF4 - NaF [352] and characterized the complexes BeF42 and BF4 as having a tetragonal configuration. Wave numbers are as follows (cm1)  

For the BF4 complex, a band corresponding to V at 773 cm 1 was observed. Additional bands were found in the range of 660-715 cm 1 and were assigned to bond vibrations of the complexes SiFs and SiF62 [352]. 

Wilmshurst [353] observed the following bands were in the IR reflection spectra of some mixtures belonging to the LiF - NaF - KF - ZrF4 system (cm1) 720, 520, 480, 240. The band at 480 cm 1 was assigned to bond vibrations of either ZrF5 or ZrF62, while bands at 520 and 240 cm 1 were 

Complexes in fluoride melts - vibration spectroscopy of fluoride melts 

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